Skip to content
https://royalsocietypublishing.org

Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
70
GRADE
C
FIX
5
REVIEW
2
PASS
6
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
79
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
98
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
77
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.18 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

2.81 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

43 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.001

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

1.78 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

3.15 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
15
6 PASS 2 REVIEW 5 FIX
F
Page Weight Budget
Action
3.6 MB transferred, 63 requests
FIX
3.6 MB transferred, 63 requests
Warning::
Page weighs 7.7 MB (3.6 MB transferred)
Warning::
Images are 2.1 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 2.1 MB
Warning::
JavaScript is 1.1 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.1 MB
Info::
63 HTTP requests
Info::
Estimated 0.75 g CO2 per page load
3.6 MB / 2.4 MB budget
3.6 MB transferred
63 requests
0.75 g CO2 per page load
Images 2.1 MiB 59%
JavaScript 1.1 MiB 31%
Fonts 177.3 KiB 5%
CSS 103.8 KiB 3%
Other 35.1 KiB 1%
HTML 18.6 KiB 1%
Other 10.2 KiB 0%
Other 4.6 KiB 0%
Other 3.4 KiB 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

D
Third-Party Impact
Action
98% third-party, 0 ms blocking
FIX
98% third-party, 0 ms blocking
Warning::
Third-party code accounts for 98% of page weight (3.5 MiB of 3.6 MiB)
Info::
Third-party blocking time is low (0 ms)
98%
First-party Third-party
F
JS Bundles
Action
15 scripts, 584 KB unused
FIX
15 scripts, 584 KB unused
Warning::
https://js.stripe.com/v3/: 164 KB unused (73%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml...: 122 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://trs.silverchair-cdn.com/Themes/Client/app/...: 104 KB unused (77%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cookie-cdn.cookiepro.com/scripttemplates/2...: 66 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-VYDH...: 66 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 584 KB
584 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://js.stripe.com/v3/225 KB164 KB (73%)✓3rd
https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js251 KB122 KB (49%)✓3rd
https://trs.silverchair-cdn.com/Themes/Client/app/jsdist/v-639116431184716663/site.min.js135 KB104 KB (77%)✓3rd
https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/otBannerSdk.js125 KB66 KB (53%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-VYDHG8C6QY&cx=c&gtm=4e64h1157 KB66 KB (42%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TFQX55T7133 KB63 KB (47%)✓3rd
https://widgets.figshare.com/static/figshare.js36 KB—✓3rd
https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/01980ead-9999-7ec5-8307-69ac7b4ebd59.json3 KB—✓3rd
https://cookie-cdn.cookiepro.com/scripttemplates/otSDKStub.js9 KB—✓3rd
https://trs.silverchair-cdn.com/Themes/Silver/app/vendor/v-639102489972463725/jquery-migrate-3.1.0.min.js4 KB—✓3rd

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

F
Page Weight Inventory
Action
63 resources · 3.6 MB · 584 KB savings available
FIX
63 resources · 3.6 MB · 584 KB savings available
Warning::
Page weight 2.6 MB over 1MB target
Got: 3.6 MB Expected: ≤ 1 MB
Info::
~584 KB of savings available
Warning::
57 third-party resources (98% of weight)
Info::
4 resources over 200KB
63 resources · 3.6 MiB · 57 third-party 2.6 MiB over 1MB target
Image 60% · 2.1 MiB
JavaScript 31% · 1.1 MiB
Font 5% · 177.3 KiB
CSS 3% · 108.8 KiB
Document 1% · 28.8 KiB
Other 1% · 22.5 KiB

~584.5 KiB of savings available

Remove unused JavaScript: 584.5 KiB
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

C
Image Optimization
Action
19 images, 0 KB saveable
REVIEW
19 images, 0 KB saveable
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/RSTAS... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/RSTBS... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://royalsocietypublishing.org/imagelibrary/TR... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/RSBLS... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/RSIFS... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/RSFSS... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/data/SiteBuilderAs... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://trs.silverchair-cdn.com/ImageLibrary/Umbre... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
19 images 2.1 MB
0 oversized -0 KB
17 legacy format
14 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

B
JS Execution Cost
817ms total JS execution
REVIEW
817ms total JS execution
Info::
https://royalsocietypublishing.org/: 203ms CPU time
Info::
https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml...: 120ms CPU time
Info::
Unattributable: 97ms CPU time
Info::
https://trs.silverchair-cdn.com/Themes/Client/app/...: 84ms CPU time
Info::
https://cookie-cdn.cookiepro.com/scripttemplates/2...: 73ms CPU time
Warning::
Third-party scripts: 560ms (69% of total)

Main Thread Breakdown

Script Evaluation 48% Other 17% Style & Layout 13% Script Parsing & Compilation 11% Rendering 7%
ScriptTotalScriptingParse/CompileParty
https://royalsocietypublishing.org/203ms8ms2ms1st
https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js120ms92ms28ms3rd
Unattributable97ms15ms0ms3rd
https://trs.silverchair-cdn.com/Themes/Client/app/jsdist/v-639116431184716663/site.min.js84ms20ms12ms3rd
https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/otBannerSdk.js73ms51ms12ms3rd
https://js.stripe.com/v3/68ms43ms24ms3rd
https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js61ms38ms2ms3rd
https://www.googletagmanager.com/gtag/js?id=G-VYDHG8C6QY&cx=c&gtm=4e64h157ms48ms9ms3rd
https://royalsocietypublishing.org/cdn-cgi/challenge-platform/scripts/jsd/main.js54ms51ms1ms1st
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
6 fonts (177 KB)
PASS
6 fonts (177 KB)
Info::
6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

6

177 KB total

Render-blocking

0

of 6

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 1.2 s LCP 2.8 shttps://use.typekit.net/af/d7ff92/00000000000000007735e609/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3l https://use.typekit.net/af/d7ff92/00000000000000007735e609/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 29.8 KiB — 20 ms — font-display: swaphttps://use.typekit.net/af/5be242/00000000000000007735e603/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3l https://use.typekit.net/af/5be242/00000000000000007735e603/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3 — 30.6 KiB — 24 ms — font-display: swaphttps://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/fonts/white-label.ttf?7yqv1cwhite-label.ttf https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/fonts/white-label.ttf?7yqv1c — 21.2 KiB — 5 ms — font-display: swaphttps://use.typekit.net/af/e37e5a/00000000000000007735e60d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3l https://use.typekit.net/af/e37e5a/00000000000000007735e60d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3 — 29.7 KiB — 20 ms — font-display: swaphttps://use.typekit.net/af/38ea3a/00000000000000007758cf7d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i7&v=3l https://use.typekit.net/af/38ea3a/00000000000000007758cf7d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i7&v=3 — 33.4 KiB — 22 ms — font-display: swaphttps://use.typekit.net/af/6eb0e3/00000000000000007758cf8f/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i4&v=3l https://use.typekit.net/af/6eb0e3/00000000000000007758cf8f/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i4&v=3 — 32.7 KiB — 24 ms — font-display: swap
l woff2 swap
Size 30 KB
Load time 20 ms
Start 782 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 31 KB
Load time 24 ms
Start 783 ms
Risk FOUT — text flashes from fallback to web font
white-label.ttf ttf swap
Size 21 KB
Load time 5 ms
Start 783 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
l woff2 swap
Size 30 KB
Load time 20 ms
Start 783 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 33 KB
Load time 22 ms
Start 783 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 33 KB
Load time 24 ms
Start 783 ms
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)

Fixing the unchecked items could save ~6 KB and ~12 ms

A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
63 requests over 2425ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 1.2 s LCP 2.8 shttps://royalsocietypublishing.org// https://royalsocietypublishing.org/ — 307 — 76 B — 61 ms — http/1.1https://royalsocietypublishing.org// https://royalsocietypublishing.org/ — 200 — 15.8 KiB — 426 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/otSDKStub.jscookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/otSDKStub.js — 200 — 9.3 KiB — 78 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3221trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3221 — -1 — 0 B — 367 ms — https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.jsajax.googleapis.com/ajax/libs/jquer... https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js — 200 — 30.7 KiB — 102 ms — h2https://trs.silverchair-cdn.com/Themes/Silver/app/vendor/v-639102489972463725/jquery-migrate-3.1.0.min.jstrs.silverchair-cdn.com/Themes/Silv... https://trs.silverchair-cdn.com/Themes/Silver/app/vendor/v-639102489972463725/jquery-migrate-3.1.0.min.js — 200 — 3.9 KiB — 21 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639116430755733296/site.min.csstrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639116430755733296/site.min.css — 200 — 98.1 KiB — 27 ms — h2https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/style.csstrs.silverchair-cdn.com/Themes/Silv... https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/style.css — 200 — 1.9 KiB — 17 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639102489049995227/bg_img.csstrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639102489049995227/bg_img.css — 200 — 687 B — 18 ms — h2https://use.typekit.net/tyr3hmc.cssuse.typekit.net/tyr3hmc.css https://use.typekit.net/tyr3hmc.css — 200 — 1.1 KiB — 15 ms — h2https://trs.silverchair-cdn.com/data/SiteBuilderAssets/Live/CSS/umbrella/v-639088486566875982/site-umbrella.csstrs.silverchair-cdn.com/data/SiteBu... https://trs.silverchair-cdn.com/data/SiteBuilderAssets/Live/CSS/umbrella/v-639088486566875982/site-umbrella.css — 200 — 1.9 KiB — 18 ms — h2https://widgets.figshare.com/static/figshare.jswidgets.figshare.com/static/figshar... https://widgets.figshare.com/static/figshare.js — 200 — 36.3 KiB — 167 ms — h2https://js.stripe.com/v3/js.stripe.com/v3/ https://js.stripe.com/v3/ — 200 — 225.4 KiB — 56 ms — h2https://trs.silverchair-cdn.com/data/SiteBuilderAssetsOriginals/Live/images/umbrella/TRS-logo-256x256-1.pngtrs.silverchair-cdn.com/data/SiteBu... https://trs.silverchair-cdn.com/data/SiteBuilderAssetsOriginals/Live/images/umbrella/TRS-logo-256x256-1.png — 200 — 15.3 KiB — 22 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/S2O.jpg?versionId=2906trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/S2O.jpg?versionId=2906 — 200 — 222.0 KiB — 10 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/5327_Energy_reserves_in_the_Arctic_Leal.jpg?versionId=3323trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/5327_Energy_reserves_in_the_Arctic_Leal.jpg?versionId=3323 — 200 — 81.8 KiB — 6 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/reviewer-rewards.jpg?versionId=3224trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/reviewer-rewards.jpg?versionId=3224 — 200 — 106.4 KiB — 5 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3230trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3230 — -1 — 0 B — 510 ms — https://trs.silverchair-cdn.com/Themes/Client/app/jsdist/v-639116431184716663/site.min.jstrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/jsdist/v-639116431184716663/site.min.js — 200 — 135.3 KiB — 10 ms — h2https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/01980ead-9999-7ec5-8307-69ac7b4ebd59.jsoncookie-cdn.cookiepro.com/consent/01... https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/01980ead-9999-7ec5-8307-69ac7b4ebd59.json — 200 — 2.6 KiB — 84 ms — h2https://p.typekit.net/p.css?s=1&k=tyr3hmc&ht=tk&f=139.140.173.174.175.176&a=126284003&app=typekit&e=cssp.typekit.net/p.css?s=1&k=tyr3hmc&h... https://p.typekit.net/p.css?s=1&k=tyr3hmc&ht=tk&f=139.140.173.174.175.176&a=126284003&app=typekit&e=css — 200 — 172 B — 19 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/manifest.jsontrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/manifest.json — 404 — 10.2 KiB — 375 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspa20251113f01.png?versionId=3221trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspa20251113f01.png?versionId=3221 — 200 — 38.8 KiB — 32 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspb.2025.2106.f001.png?versionId=3225trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspb.2025.2106.f001.png?versionId=3225 — 200 — 65.8 KiB — 18 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rsos.252055.f001.png?versionId=3226trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rsos.252055.f001.png?versionId=3226 — 200 — 21.0 KiB — 17 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSTASelfServe/Latest_Issues/DM0425_widget.jpg?versionId=3227trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSTASelfServe/Latest_Issues/DM0425_widget.jpg?versionId=3227 — 200 — 66.0 KiB — 27 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSTBSelfServe/Latest_issues/rstb.381.1947.jpg?versionId=3228trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSTBSelfServe/Latest_issues/rstb.381.1947.jpg?versionId=3228 — 200 — 109.9 KiB — 28 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSFSSelfServe/Latest_issues/rsfs.2025.15.issue-5.largecover.jpeg?versionId=3045trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSFSSelfServe/Latest_issues/rsfs.2025.15.issue-5.largecover.jpeg?versionId=3045 — 200 — 147.2 KiB — 41 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSBLSelfServe/related-content/Hedgehog.png?versionId=3229trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSBLSelfServe/related-content/Hedgehog.png?versionId=3229 — 200 — 137.8 KiB — 36 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSIFSelfServe/related-content/interface-anniversary-prize-winner.jpg?versionId=3230trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSIFSelfServe/related-content/interface-anniversary-prize-winner.jpg?versionId=3230 — 200 — 128.3 KiB — 42 ms — h2
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 1.2 s LCP 2.8 shttps://royalsocietypublishing.org// https://royalsocietypublishing.org/ — 307 — 76 B — 61 ms — http/1.1https://royalsocietypublishing.org// https://royalsocietypublishing.org/ — 200 — 15.8 KiB — 426 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/otSDKStub.jscookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/otSDKStub.js — 200 — 9.3 KiB — 78 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3221trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3221 — -1 — 0 B — 367 ms — https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.jsajax.googleapis.com/ajax/libs/jquer... https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js — 200 — 30.7 KiB — 102 ms — h2https://trs.silverchair-cdn.com/Themes/Silver/app/vendor/v-639102489972463725/jquery-migrate-3.1.0.min.jstrs.silverchair-cdn.com/Themes/Silv... https://trs.silverchair-cdn.com/Themes/Silver/app/vendor/v-639102489972463725/jquery-migrate-3.1.0.min.js — 200 — 3.9 KiB — 21 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639116430755733296/site.min.csstrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639116430755733296/site.min.css — 200 — 98.1 KiB — 27 ms — h2https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/style.csstrs.silverchair-cdn.com/Themes/Silv... https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/style.css — 200 — 1.9 KiB — 17 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639102489049995227/bg_img.csstrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/css/v-639102489049995227/bg_img.css — 200 — 687 B — 18 ms — h2https://use.typekit.net/tyr3hmc.cssuse.typekit.net/tyr3hmc.css https://use.typekit.net/tyr3hmc.css — 200 — 1.1 KiB — 15 ms — h2https://trs.silverchair-cdn.com/data/SiteBuilderAssets/Live/CSS/umbrella/v-639088486566875982/site-umbrella.csstrs.silverchair-cdn.com/data/SiteBu... https://trs.silverchair-cdn.com/data/SiteBuilderAssets/Live/CSS/umbrella/v-639088486566875982/site-umbrella.css — 200 — 1.9 KiB — 18 ms — h2https://widgets.figshare.com/static/figshare.jswidgets.figshare.com/static/figshar... https://widgets.figshare.com/static/figshare.js — 200 — 36.3 KiB — 167 ms — h2https://js.stripe.com/v3/js.stripe.com/v3/ https://js.stripe.com/v3/ — 200 — 225.4 KiB — 56 ms — h2https://trs.silverchair-cdn.com/data/SiteBuilderAssetsOriginals/Live/images/umbrella/TRS-logo-256x256-1.pngtrs.silverchair-cdn.com/data/SiteBu... https://trs.silverchair-cdn.com/data/SiteBuilderAssetsOriginals/Live/images/umbrella/TRS-logo-256x256-1.png — 200 — 15.3 KiB — 22 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/S2O.jpg?versionId=2906trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/S2O.jpg?versionId=2906 — 200 — 222.0 KiB — 10 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/5327_Energy_reserves_in_the_Arctic_Leal.jpg?versionId=3323trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/5327_Energy_reserves_in_the_Arctic_Leal.jpg?versionId=3323 — 200 — 81.8 KiB — 6 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/reviewer-rewards.jpg?versionId=3224trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/reviewer-rewards.jpg?versionId=3224 — 200 — 106.4 KiB — 5 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3230trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/rsta.2025.383.issue-2304.largecover.jpg?versionId=3230 — -1 — 0 B — 510 ms — https://trs.silverchair-cdn.com/Themes/Client/app/jsdist/v-639116431184716663/site.min.jstrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/jsdist/v-639116431184716663/site.min.js — 200 — 135.3 KiB — 10 ms — h2https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/01980ead-9999-7ec5-8307-69ac7b4ebd59.jsoncookie-cdn.cookiepro.com/consent/01... https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/01980ead-9999-7ec5-8307-69ac7b4ebd59.json — 200 — 2.6 KiB — 84 ms — h2https://p.typekit.net/p.css?s=1&k=tyr3hmc&ht=tk&f=139.140.173.174.175.176&a=126284003&app=typekit&e=cssp.typekit.net/p.css?s=1&k=tyr3hmc&h... https://p.typekit.net/p.css?s=1&k=tyr3hmc&ht=tk&f=139.140.173.174.175.176&a=126284003&app=typekit&e=css — 200 — 172 B — 19 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/manifest.jsontrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/manifest.json — 404 — 10.2 KiB — 375 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspa20251113f01.png?versionId=3221trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspa20251113f01.png?versionId=3221 — 200 — 38.8 KiB — 32 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspb.2025.2106.f001.png?versionId=3225trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rspb.2025.2106.f001.png?versionId=3225 — 200 — 65.8 KiB — 18 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rsos.252055.f001.png?versionId=3226trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/rsos.252055.f001.png?versionId=3226 — 200 — 21.0 KiB — 17 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSTASelfServe/Latest_Issues/DM0425_widget.jpg?versionId=3227trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSTASelfServe/Latest_Issues/DM0425_widget.jpg?versionId=3227 — 200 — 66.0 KiB — 27 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSTBSelfServe/Latest_issues/rstb.381.1947.jpg?versionId=3228trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSTBSelfServe/Latest_issues/rstb.381.1947.jpg?versionId=3228 — 200 — 109.9 KiB — 28 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSFSSelfServe/Latest_issues/rsfs.2025.15.issue-5.largecover.jpeg?versionId=3045trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSFSSelfServe/Latest_issues/rsfs.2025.15.issue-5.largecover.jpeg?versionId=3045 — 200 — 147.2 KiB — 41 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSBLSelfServe/related-content/Hedgehog.png?versionId=3229trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSBLSelfServe/related-content/Hedgehog.png?versionId=3229 — 200 — 137.8 KiB — 36 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/RSIFSelfServe/related-content/interface-anniversary-prize-winner.jpg?versionId=3230trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/RSIFSelfServe/related-content/interface-anniversary-prize-winner.jpg?versionId=3230 — 200 — 128.3 KiB — 42 ms — h2https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/SidnieManton.jpg?versionId=3232trs.silverchair-cdn.com/ImageLibrar... https://trs.silverchair-cdn.com/ImageLibrary/UmbrellaSelfServeAssets/SidnieManton.jpg?versionId=3232 — 200 — 45.6 KiB — 38 ms — h2https://royalsocietypublishing.org/imagelibrary/TRS-logo-association.png/imagelibrary/TRS-logo-association.... https://royalsocietypublishing.org/imagelibrary/TRS-logo-association.png — 200 — 41.5 KiB — 33 ms — h2https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.jscdn.jsdelivr.net/npm/mathjax@3/es5/... https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js — 200 — 251.1 KiB — 42 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-TFQX55T7www.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-TFQX55T7 — 200 — 133.4 KiB — 144 ms — h2https://geolocation.onetrust.com/cookieconsentpub/v1/geo/locationgeolocation.onetrust.com/cookiecons... https://geolocation.onetrust.com/cookieconsentpub/v1/geo/location — 200 — 303 B — 107 ms — h2https://trs.silverchair-cdn.com/data/SiteBuilderAssetsOriginals/Live/Images/umbrella/hero-background.jpgtrs.silverchair-cdn.com/data/SiteBu... https://trs.silverchair-cdn.com/data/SiteBuilderAssetsOriginals/Live/Images/umbrella/hero-background.jpg — 200 — 895.8 KiB — 23 ms — h2https://use.typekit.net/af/d7ff92/00000000000000007735e609/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3use.typekit.net/af/d7ff92/000000000... https://use.typekit.net/af/d7ff92/00000000000000007735e609/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 200 — 29.8 KiB — 20 ms — h2https://use.typekit.net/af/5be242/00000000000000007735e603/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3use.typekit.net/af/5be242/000000000... https://use.typekit.net/af/5be242/00000000000000007735e603/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3 — 200 — 30.6 KiB — 24 ms — h2https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/fonts/white-label.ttf?7yqv1ctrs.silverchair-cdn.com/Themes/Silv... https://trs.silverchair-cdn.com/Themes/Silver/app/icons/v-639102489936978178/fonts/white-label.ttf?7yqv1c — 200 — 21.2 KiB — 5 ms — h2https://use.typekit.net/af/e37e5a/00000000000000007735e60d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3use.typekit.net/af/e37e5a/000000000... https://use.typekit.net/af/e37e5a/00000000000000007735e60d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3 — 200 — 29.7 KiB — 20 ms — h2https://use.typekit.net/af/38ea3a/00000000000000007758cf7d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i7&v=3use.typekit.net/af/38ea3a/000000000... https://use.typekit.net/af/38ea3a/00000000000000007758cf7d/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i7&v=3 — 200 — 33.4 KiB — 22 ms — h2https://use.typekit.net/af/6eb0e3/00000000000000007758cf8f/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i4&v=3use.typekit.net/af/6eb0e3/000000000... https://use.typekit.net/af/6eb0e3/00000000000000007758cf8f/31/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=i4&v=3 — 200 — 32.7 KiB — 24 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/otBannerSdk.jscookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/otBannerSdk.js — 200 — 124.6 KiB — 56 ms — h2https://royalsocietypublishing.org/cdn-cgi/challenge-platform/scripts/jsd/main.js/cdn-cgi/challenge-platform/scripts... https://royalsocietypublishing.org/cdn-cgi/challenge-platform/scripts/jsd/main.js — 302 — 385 B — 55 ms — h2https://royalsocietypublishing.org/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/main.js?/cdn-cgi/challenge-platform/h/b/scr... https://royalsocietypublishing.org/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/main.js? — 200 — 12.9 KiB — 23 ms — h2https://royalsocietypublishing.org/cdn-cgi/challenge-platform/h/b/jsd/oneshot/0b8fb825cb67/0.2889736943988933:1776798611:JhAcgcFTqWduhobqPOYGc2dNFUeO_MBVB4fG2J7bOao/9eff1fa0de415dcd/cdn-cgi/challenge-platform/h/b/jsd... https://royalsocietypublishing.org/cdn-cgi/challenge-platform/h/b/jsd/oneshot/0b8fb825cb67/0.2889736943988933:1776798611:JhAcgcFTqWduhobqPOYGc2dNFUeO_MBVB4fG2J7bOao/9eff1fa0de415dcd — 200 — 1.2 KiB — 40 ms — h2https://www.googletagmanager.com/gtag/js?id=G-VYDHG8C6QY&cx=c&gtm=4e64h1www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-VYDHG8C6QY&cx=c&gtm=4e64h1 — 200 — 157.1 KiB — 53 ms — h2https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/0199abcb-a8b9-75dc-ab01-6e793377ed9b/en.jsoncookie-cdn.cookiepro.com/consent/01... https://cookie-cdn.cookiepro.com/consent/01980ead-9999-7ec5-8307-69ac7b4ebd59/0199abcb-a8b9-75dc-ab01-6e793377ed9b/en.json — 200 — 9.3 KiB — 41 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/otFlat.jsoncookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/otFlat.json — 200 — 3.5 KiB — 33 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/v2/otPcPanel.jsoncookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/v2/otPcPanel.json — 200 — 13.8 KiB — 35 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/otCookieSettingsButton.jsoncookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/otCookieSettingsButton.json — 200 — 2.1 KiB — 31 ms — h2https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/otCommonStyles.csscookie-cdn.cookiepro.com/scripttemp... https://cookie-cdn.cookiepro.com/scripttemplates/202511.1.0/assets/otCommonStyles.css — 200 — 5.0 KiB — 33 ms — h2https://region1.google-analytics.com/g/collect?v=2&tid=G-VYDHG8C6QY&gtm=45je64h1v9230707606z89230704617za20gzb9230704617zd9230704617&_p=1776803185263&gcs=G100&gcd=13p3p3p2p5l1&npa=1&dma_cps=-&dma=1&are=1&cid=1784039634.1776803186&frm=0&pscdl=denied&rcb=2&sr=800x600&uaa=x86&uab=64&uafvl=Chromium%3B147.0.7727.101%7CNot.A%252FBrand%3B8.0.0.0&uam=&uamb=0&uap=macOS&uapv=10.15.7&uaw=0&ul=en-us&_s=1&tag_exp=0~115616986~115938466~115938468~117266400~118128922&sid=1776803185&sct=1&seg=0&dl=https%3A%2F%2Froyalsocietypublishing.org%2F&dt=The%20Royal%20Society&_tu=CA&en=page_view&_fv=1&_nsi=1&_ss=1&tfd=1255region1.google-analytics.com/g/coll... https://region1.google-analytics.com/g/collect?v=2&tid=G-VYDHG8C6QY&gtm=45je64h1v9230707606z89230704617za20gzb9230704617zd9230704617&_p=1776803185263&gcs=G100&gcd=13p3p3p2p5l1&npa=1&dma_cps=-&dma=1&are=1&cid=1784039634.1776803186&frm=0&pscdl=denied&rcb=2&sr=800x600&uaa=x86&uab=64&uafvl=Chromium%3B147.0.7727.101%7CNot.A%252FBrand%3B8.0.0.0&uam=&uamb=0&uap=macOS&uapv=10.15.7&uaw=0&ul=en-us&_s=1&tag_exp=0~115616986~115938466~115938468~117266400~118128922&sid=1776803185&sct=1&seg=0&dl=https%3A%2F%2Froyalsocietypublishing.org%2F&dt=The%20Royal%20Society&_tu=CA&en=page_view&_fv=1&_nsi=1&_ss=1&tfd=1255 — 204 — 556 B — 77 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/manifest.jsontrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/manifest.json — 404 — 0 B — 2 ms — h2https://cookie-cdn.cookiepro.com/logos/static/ot_guard_logo.svgcookie-cdn.cookiepro.com/logos/stat... https://cookie-cdn.cookiepro.com/logos/static/ot_guard_logo.svg — 200 — 741 B — 34 ms — h2https://cookie-cdn.cookiepro.com/logos/5a3224e5-ab28-43ab-b955-60f64c7159db/01980ead-9999-7ec5-8307-69ac7b4ebd59/9d7bd07f-3d39-4883-a7e8-53a3b14e528a/OneTrust_Logo.jpgcookie-cdn.cookiepro.com/logos/5a32... https://cookie-cdn.cookiepro.com/logos/5a3224e5-ab28-43ab-b955-60f64c7159db/01980ead-9999-7ec5-8307-69ac7b4ebd59/9d7bd07f-3d39-4883-a7e8-53a3b14e528a/OneTrust_Logo.jpg — 200 — 57.9 KiB — 36 ms — h2https://cookie-cdn.cookiepro.com/logos/static/poweredBy_cp_logo.svgcookie-cdn.cookiepro.com/logos/stat... https://cookie-cdn.cookiepro.com/logos/static/poweredBy_cp_logo.svg — 200 — 2.7 KiB — 37 ms — h2https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/v-639102489050295255/favicon.icotrs.silverchair-cdn.com/Themes/Clie... https://trs.silverchair-cdn.com/Themes/Client/app/img/favicons/v-639102489050295255/favicon.ico — 200 — 2.9 KiB — 6 ms — h2https://js.stripe.com/v3/m-outer-3437aaddcdf6922d623e172c2d6f9278.htmljs.stripe.com/v3/m-outer-3437aaddcd... https://js.stripe.com/v3/m-outer-3437aaddcdf6922d623e172c2d6f9278.html — 200 — 1.0 KiB — 12 ms — h3https://js.stripe.com/v3/fingerprinted/js/m-outer-15a2b40a058ddff1cffdb63779fe3de1.jsjs.stripe.com/v3/fingerprinted/js/m... https://js.stripe.com/v3/fingerprinted/js/m-outer-15a2b40a058ddff1cffdb63779fe3de1.js — 200 — 895 B — 5 ms — h3https://m.stripe.network/inner.htmlm.stripe.network/inner.html https://m.stripe.network/inner.html — 200 — 1.8 KiB — 16 ms — h2https://m.stripe.network/out-4.5.45.jsm.stripe.network/out-4.5.45.js https://m.stripe.network/out-4.5.45.js — 200 — 16.5 KiB — 6 ms — h2https://m.stripe.com/6m.stripe.com/6 https://m.stripe.com/6 — 200 — 580 B — 550 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
69% of JavaScript execution is third-party
First-party Third-party 560ms · 924KB · $7/mo
jsDelivr
CDN
Optional
Execution 120ms
Transfer 251 KB
Unused 49%
Monthly Cost $2/mo
Unattributable
Other
Optional
Execution 97ms
Transfer 0 KB
Monthly Cost $1/mo
trs.silverchair-cdn.com
Other
Optional
Execution 84ms
Transfer 135 KB
Unused 77%
Monthly Cost $1/mo
cookie-cdn.cookiepro.com
Other
Optional
Execution 73ms
Transfer 125 KB
Unused 53%
Monthly Cost $1/mo
Stripe
Payment
Essential
Execution 68ms
Transfer 225 KB
Unused 73%
Monthly Cost $1/mo
ajax.googleapis.com
Other
Optional
Execution 61ms
Transfer 31 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 57ms
Transfer 157 KB
Unused 42%
Monthly Cost $1/mo

69% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

77% of trs.silverchair-cdn.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

53% of cookie-cdn.cookiepro.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

73% of Stripe's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

Send Feedback