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https://royalsociety.org

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
84
GRADE
B
FIX
1
REVIEW
6
PASS
8
INFO
2

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

Mobile Desktop
60
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.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

3.35 s

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

9.85 s

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

237 ms

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

0.000

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

5.85 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.

9.85 s

Page Load Progression

413 ms
825 ms
1.2 s
1.7 s
2.1 s
2.5 s
2.9 s
3.3 s
Checks
17
8 PASS 6 REVIEW 1 FIX
D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: no-cache, no-store
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-cache, no-store

DirectiveValueMeaning
no-cache—Cache but always revalidate first
no-store—Never cache this response
B
Page Weight Budget
1.4 MB transferred, 36 requests
REVIEW
1.4 MB transferred, 36 requests
Info::
Page weighs 2.4 MB (1.4 MB transferred)
Info::
36 HTTP requests
Info::
Estimated 0.29 g CO2 per page load
1.4 MB / 2.4 MB budget
1.4 MB transferred
36 requests
0.29 g CO2 per page load
Images 792.5 KiB 55%
JavaScript 356.2 KiB 25%
HTML 100.3 KiB 7%
Fonts 97.2 KiB 7%
Other 35.0 KiB 2%
CSS 27.1 KiB 2%
Other 19.4 KiB 1%
Other 2.3 KiB 0%
0 2.4 MB 4.9 MB
Under budget
C
Image Optimization
Action
6 images, 0 KB saveable
REVIEW
6 images, 0 KB saveable
Warning::
https://royalsociety.org/assets/images/logo@2x.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://royalsociety.org/url(/-/media/navigation/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
6 images 793 KB
0 oversized -0 KB
6 legacy format
2 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

C
JS Execution Cost
Action
1484ms total JS execution
REVIEW
1484ms total JS execution
Warning::
https://royalsociety.org/assets/js/main.js: 601ms CPU time
Warning::
Unattributable: 288ms CPU time
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-NS6...: 260ms CPU time
Info::
https://cdn-ukwest.onetrust.com/scripttemplates/20...: 218ms CPU time
Info::
https://royalsociety.org/: 117ms CPU time
Warning::
Third-party scripts: 766ms (52% of total)

Main Thread Breakdown

Script Evaluation 44% Other 28% Style & Layout 15% Script Parsing & Compilation 7% Rendering 3% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
https://royalsociety.org/assets/js/main.js601ms200ms15ms1st
Unattributable288ms77ms0ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-NS67FDG260ms207ms44ms3rd
https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/otBannerSdk.js218ms141ms45ms3rd
https://royalsociety.org/117ms7ms4ms1st
C
JS Bundles
Action
12 scripts, 165 KB unused
REVIEW
12 scripts, 165 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-NS6...: 84 KB unused (50%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn-ukwest.onetrust.com/scripttemplates/20...: 55 KB unused (52%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://royalsociety.org/assets/js/main.js: 26 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 165 KB
165 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-NS67FDG169 KB84 KB (50%)✓3rd
https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/otBannerSdk.js104 KB55 KB (52%)✓3rd
https://royalsociety.org/assets/js/main.js54 KB26 KB (49%)✓1st
https://cdn-ukwest.onetrust.com/scripttemplates/otSDKStub.js9 KB—✓3rd
https://cdn-ukwest.onetrust.com/consent/c343a84c-eec8-4e9a-a16b-69278300c712/c343a84c-eec8-4e9a-a16b-69278300c712.json2 KB—✓3rd
https://royalsociety.org/assets/js/328.4e865f0ff4b6617398bf.js3 KB—✓1st
https://royalsociety.org/assets/js/374.d9906402510d7122eae4.js2 KB—✓1st
https://royalsociety.org/assets/js/799.c9cdc01946610cfc5be8.js5 KB—✓1st
https://royalsociety.org/assets/js/803.a16ce658ac8316e1725f.js4 KB—✓1st
https://cdn-ukwest.onetrust.com/consent/c343a84c-eec8-4e9a-a16b-69278300c712/018dd5ec-e5d8-7fa4-9da4-b7f3f6c5b33f/en.json15 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

C
Page Weight Inventory
Action
36 resources · 1.4 MB · 165 KB savings available
REVIEW
36 resources · 1.4 MB · 165 KB savings available
Warning::
Page weight 406 KB over 1MB target
Got: 1.4 MB Expected: ≤ 1 MB
Info::
~165 KB of savings available
Info::
17 third-party resources (30% of weight)
Info::
1 resources over 200KB
36 resources · 1.4 MiB · 17 third-party 406.1 KiB over 1MB target
Image 57% · 810.7 KiB
JavaScript 26% · 373.0 KiB
Document 7% · 102.0 KiB
Font 7% · 97.2 KiB
CSS 2% · 30.9 KiB
Other 1% · 16.2 KiB

~164.8 KiB of savings available

Remove unused JavaScript: 164.8 KiB
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Third-Party Impact
30% third-party, 0 ms blocking
PASS
30% third-party, 0 ms blocking
Info::
Third-party code accounts for 30% of page weight (431.8 KiB of 1.4 MiB)
Info::
Third-party blocking time is low (0 ms)
70%
30%
First-party Third-party
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 (97 KB)
PASS
6 fonts (97 KB)
Info::
6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

6

97 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 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s FCP 3.4 s LCP 9.9 shttps://use.typekit.net/af/78aca8/00000000000000007735e60d/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3l https://use.typekit.net/af/78aca8/00000000000000007735e60d/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3 — 29.3 KiB — 309 ms — font-display: swaphttps://use.typekit.net/af/efe4a5/00000000000000007735e609/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3l https://use.typekit.net/af/efe4a5/00000000000000007735e609/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 29.3 KiB — 309 ms — font-display: swaphttps://royalsociety.org/assets/webfonts/fa-solid-900.woff2fa-solid-900.woff2 https://royalsociety.org/assets/webfonts/fa-solid-900.woff2 — 2.3 KiB — 116 ms — font-display: swaphttps://royalsociety.org/assets/webfonts/fa-regular-400.woff2fa-regular-400.woff2 https://royalsociety.org/assets/webfonts/fa-regular-400.woff2 — 3.3 KiB — 139 ms — font-display: swaphttps://use.typekit.net/af/2555e1/00000000000000007735e603/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3l https://use.typekit.net/af/2555e1/00000000000000007735e603/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3 — 30.2 KiB — 310 ms — font-display: swaphttps://royalsociety.org/assets/webfonts/fa-brands-400.woff2fa-brands-400.woff2 https://royalsociety.org/assets/webfonts/fa-brands-400.woff2 — 2.8 KiB — 116 ms — font-display: swap
l woff2 swap
Size 29 KB
Load time 309 ms
Start 1.0 s
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 29 KB
Load time 309 ms
Start 1.0 s
Risk FOUT — text flashes from fallback to web font
fa-solid-900.woff2 woff2 swap
Size 2 KB
Load time 116 ms
Start 1.0 s
Risk FOUT — text flashes from fallback to web font
fa-regular-400.woff2 woff2 swap
Size 3 KB
Load time 139 ms
Start 1.0 s
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 30 KB
Load time 310 ms
Start 1.0 s
Risk FOUT — text flashes from fallback to web font
fa-brands-400.woff2 woff2 swap
Size 3 KB
Load time 116 ms
Start 1.0 s
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)
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+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
36 requests over 1821ms
INFO
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s FCP 3.4 s LCP 9.9 shttps://royalsociety.org// https://royalsociety.org/ — 200 — 100.3 KiB — 198 ms — h2https://royalsociety.org/assets/css/main.css/assets/css/main.css https://royalsociety.org/assets/css/main.css — 200 — 24.9 KiB — 67 ms — h2https://royalsociety.org/assets/css/custom.css/assets/css/custom.css https://royalsociety.org/assets/css/custom.css — 200 — 948 B — 61 ms — h2https://royalsociety.org/assets/images/logo@2x.png/assets/images/logo@2x.png https://royalsociety.org/assets/images/logo@2x.png — 200 — 9.9 KiB — 58 ms — h2https://royalsociety.org/-/media/science-book-prize/ypbp/2025/winner-2025-ypbp-ceremony.jpg/-/media/science-book-prize/ypbp/20... https://royalsociety.org/-/media/science-book-prize/ypbp/2025/winner-2025-ypbp-ceremony.jpg — 200 — 57.1 KiB — 66 ms — h2https://royalsociety.org/url(/-/media/navigation/footer/logoalt2x.png);/url(/-/media/navigation/footer/log... https://royalsociety.org/url(/-/media/navigation/footer/logoalt2x.png); — 200 — 41.9 KiB — 65 ms — h2https://use.typekit.net/onn5raf.cssuse.typekit.net/onn5raf.css https://use.typekit.net/onn5raf.css — 200 — 1.0 KiB — 380 ms — h2https://royalsociety.org/assets/js/main.js/assets/js/main.js https://royalsociety.org/assets/js/main.js — 200 — 54.1 KiB — 60 ms — h2https://p.typekit.net/p.css?s=1&k=onn5raf&ht=tk&f=139.140.173.174.175.176&a=92742846&app=typekit&e=cssp.typekit.net/p.css?s=1&k=onn5raf&h... https://p.typekit.net/p.css?s=1&k=onn5raf&ht=tk&f=139.140.173.174.175.176&a=92742846&app=typekit&e=css — 200 — 172 B — 360 ms — h2https://royalsociety.org/-/media/current-topics/des8801_website-transformation-project_images_new-technologies.jpg/-/media/current-topics/des8801_web... https://royalsociety.org/-/media/current-topics/des8801_website-transformation-project_images_new-technologies.jpg — 200 — 661.8 KiB — 178 ms — h2https://use.typekit.net/af/78aca8/00000000000000007735e60d/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3use.typekit.net/af/78aca8/000000000... https://use.typekit.net/af/78aca8/00000000000000007735e60d/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n6&v=3 — 200 — 29.3 KiB — 309 ms — h2https://use.typekit.net/af/efe4a5/00000000000000007735e609/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3use.typekit.net/af/efe4a5/000000000... https://use.typekit.net/af/efe4a5/00000000000000007735e609/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 200 — 29.3 KiB — 309 ms — h2https://royalsociety.org/assets/webfonts/fa-solid-900.woff2/assets/webfonts/fa-solid-900.woff2 https://royalsociety.org/assets/webfonts/fa-solid-900.woff2 — 200 — 2.3 KiB — 116 ms — h2https://royalsociety.org/assets/webfonts/fa-regular-400.woff2/assets/webfonts/fa-regular-400.wof... https://royalsociety.org/assets/webfonts/fa-regular-400.woff2 — 200 — 3.3 KiB — 139 ms — h2https://use.typekit.net/af/2555e1/00000000000000007735e603/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3use.typekit.net/af/2555e1/000000000... https://use.typekit.net/af/2555e1/00000000000000007735e603/30/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3 — 200 — 30.2 KiB — 310 ms — h2https://royalsociety.org/assets/webfonts/fa-brands-400.woff2/assets/webfonts/fa-brands-400.woff... https://royalsociety.org/assets/webfonts/fa-brands-400.woff2 — 200 — 2.8 KiB — 116 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-NS67FDGwww.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-NS67FDG — 200 — 169.2 KiB — 203 ms — h2https://cdn-ukwest.onetrust.com/scripttemplates/otSDKStub.jscdn-ukwest.onetrust.com/scripttempl... https://cdn-ukwest.onetrust.com/scripttemplates/otSDKStub.js — 200 — 9.1 KiB — 104 ms — h2https://cdn-ukwest.onetrust.com/consent/c343a84c-eec8-4e9a-a16b-69278300c712/c343a84c-eec8-4e9a-a16b-69278300c712.jsoncdn-ukwest.onetrust.com/consent/c34... https://cdn-ukwest.onetrust.com/consent/c343a84c-eec8-4e9a-a16b-69278300c712/c343a84c-eec8-4e9a-a16b-69278300c712.json — 200 — 2.1 KiB — 77 ms — h2https://royalsociety.org/assets/js/328.4e865f0ff4b6617398bf.js/assets/js/328.4e865f0ff4b6617398bf... https://royalsociety.org/assets/js/328.4e865f0ff4b6617398bf.js — 200 — 3.3 KiB — 55 ms — h2https://royalsociety.org/assets/icons/favicon-32x32.png/assets/icons/favicon-32x32.png https://royalsociety.org/assets/icons/favicon-32x32.png — 404 — 1.7 KiB — 114 ms — h2https://royalsociety.org/assets/js/374.d9906402510d7122eae4.js/assets/js/374.d9906402510d7122eae4... https://royalsociety.org/assets/js/374.d9906402510d7122eae4.js — 200 — 2.1 KiB — 70 ms — h2https://geolocation.onetrust.com/cookieconsentpub/v1/geo/locationgeolocation.onetrust.com/cookiecons... https://geolocation.onetrust.com/cookieconsentpub/v1/geo/location — 200 — 203 B — 70 ms — h2https://royalsociety.org/assets/icons/favicon-16x16.png/assets/icons/favicon-16x16.png https://royalsociety.org/assets/icons/favicon-16x16.png — 200 — 17.7 KiB — 58 ms — h2https://royalsociety.org/assets/js/799.c9cdc01946610cfc5be8.js/assets/js/799.c9cdc01946610cfc5be8... https://royalsociety.org/assets/js/799.c9cdc01946610cfc5be8.js — 200 — 5.0 KiB — 65 ms — h2https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/otBannerSdk.jscdn-ukwest.onetrust.com/scripttempl... https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/otBannerSdk.js — 200 — 104.5 KiB — 49 ms — h2https://royalsociety.org/assets/js/803.a16ce658ac8316e1725f.js/assets/js/803.a16ce658ac8316e1725f... https://royalsociety.org/assets/js/803.a16ce658ac8316e1725f.js — 200 — 4.2 KiB — 85 ms — h2https://cdn-ukwest.onetrust.com/consent/c343a84c-eec8-4e9a-a16b-69278300c712/018dd5ec-e5d8-7fa4-9da4-b7f3f6c5b33f/en.jsoncdn-ukwest.onetrust.com/consent/c34... https://cdn-ukwest.onetrust.com/consent/c343a84c-eec8-4e9a-a16b-69278300c712/018dd5ec-e5d8-7fa4-9da4-b7f3f6c5b33f/en.json — 200 — 14.6 KiB — 40 ms — h2https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/assets/otFlat.jsoncdn-ukwest.onetrust.com/scripttempl... https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/assets/otFlat.json — 200 — 3.3 KiB — 34 ms — h2https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/assets/v2/otPcPanel.jsoncdn-ukwest.onetrust.com/scripttempl... https://cdn-ukwest.onetrust.com/scripttemplates/202401.2.0/assets/v2/otPcPanel.json — 200 — 12.7 KiB — 35 ms — h2
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s FCP 3.4 s LCP 9.9 shttps://royalsociety.org// https://royalsociety.org/ — 200 — 100.3 KiB — 198 ms — h2https://royalsociety.org/assets/css/main.css/assets/css/main.css https://royalsociety.org/assets/css/main.css — 200 — 24.9 KiB — 67 ms — h2https://royalsociety.org/assets/css/custom.css/assets/css/custom.css https://royalsociety.org/assets/css/custom.css — 200 — 948 B — 61 ms — h2https://royalsociety.org/assets/images/logo@2x.png/assets/images/logo@2x.png https://royalsociety.org/assets/images/logo@2x.png — 200 — 9.9 KiB — 58 ms — h2https://royalsociety.org/-/media/science-book-prize/ypbp/2025/winner-2025-ypbp-ceremony.jpg/-/media/science-book-prize/ypbp/20... https://royalsociety.org/-/media/science-book-prize/ypbp/2025/winner-2025-ypbp-ceremony.jpg — 200 — 57.1 KiB — 66 ms — h2https://royalsociety.org/url(/-/media/navigation/footer/logoalt2x.png);/url(/-/media/navigation/footer/log... 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HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
52% of JavaScript execution is third-party
First-party Third-party 766ms · 274KB · $10/mo
Unattributable
Other
Costly
Execution 288ms
Transfer 0 KB
Monthly Cost $4/mo
Google Tag Manager
Tag Manager
Costly
Execution 260ms
Transfer 169 KB
Unused 50%
Monthly Cost $3/mo
cdn-ukwest.onetrust.com
Other
Costly
Execution 218ms
Transfer 104 KB
Unused 52%
Monthly Cost $3/mo

These scripts may cost more than they're worth

  • Unattributable adds 288ms and costs ~$4/month
  • Google Tag Manager adds 260ms and costs ~$3/month
  • cdn-ukwest.onetrust.com adds 218ms and costs ~$3/month

52% 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

Unattributable takes 288ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Google Tag Manager takes 260ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

cdn-ukwest.onetrust.com takes 218ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

52% of cdn-ukwest.onetrust.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

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.

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