Skip to content
https://peerj.com

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
71
GRADE
C
FIX
5
REVIEW
2
PASS
8
INFO
2

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

Mobile Desktop
44
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
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.
100
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.

12.06 s

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

16.81 s

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

455 ms

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

0.013

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

12.06 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.

16.98 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
17
8 PASS 2 REVIEW 5 FIX
D
Page Weight Budget
Action
2.4 MB transferred, 59 requests
FIX
2.4 MB transferred, 59 requests
Info::
Page weighs 6.6 MB (2.4 MB transferred)
Warning::
JavaScript is 1.2 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.2 MB
Info::
Fonts are 433 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 433 KB
Info::
59 HTTP requests
Info::
Estimated 0.51 g CO2 per page load
2.4 MB / 2.4 MB budget
2.4 MB transferred
59 requests
0.51 g CO2 per page load
JavaScript 1.2 MiB 50%
Images 544.5 KiB 22%
Fonts 433.4 KiB 18%
CSS 187.9 KiB 8%
Other 32.0 KiB 1%
Other 12.7 KiB 1%
HTML 10.1 KiB 0%
Other 5.9 KiB 0%
Other 1.8 KiB 0%
0 2.4 MB 4.9 MB
Approaching limit

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

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

D
Third-Party Impact
Action
90% third-party, 0 ms blocking
FIX
90% third-party, 0 ms blocking
Warning::
Third-party code accounts for 90% of page weight (2.2 MiB of 2.4 MiB)
Info::
Third-party blocking time is low (0 ms)
90%
First-party Third-party
D
JS Execution Cost
Action
3465ms total JS execution
FIX
3465ms total JS execution
Warning::
https://cdn.peerj.com/cb040aa/webpack/peerj-app.6c...: 858ms CPU time
Warning::
https://cdn.peerj.com/cb040aa/webpack/1042.5ccb850...: 604ms CPU time
Warning::
Unattributable: 338ms CPU time
Warning::
https://cdn.peerj.com/cb040aa/webpack/1009.ce1d475...: 324ms CPU time
Warning::
https://cdn.peerj.com/cb040aa/webpack/398.8481fb5e...: 297ms CPU time
Warning::
Third-party scripts: 3009ms (87% of total)

Main Thread Breakdown

Script Evaluation 63% Other 12% Style & Layout 11% Script Parsing & Compilation 9%
ScriptTotalScriptingParse/CompileParty
https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js858ms569ms170ms3rd
https://cdn.peerj.com/cb040aa/webpack/1042.5ccb8502.js604ms467ms0ms3rd
Unattributable338ms127ms0ms3rd
https://cdn.peerj.com/cb040aa/webpack/1009.ce1d475f.js324ms266ms6ms3rd
https://cdn.peerj.com/cb040aa/webpack/398.8481fb5e.js297ms219ms1ms3rd
https://peerj.com/265ms38ms7ms1st
https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js201ms174ms24ms3rd
https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.js181ms153ms21ms3rd
https://cdn.peerj.com/cb040aa/webpack/330.a5145fec.js140ms74ms29ms3rd
https://peerj.com/js/8d39319-582a9a0.js96ms34ms27ms1st

Showing top 10 of 12 scripts

F
JS Bundles
Action
25 scripts, 684 KB unused
FIX
25 scripts, 684 KB unused
Warning::
https://cdn.peerj.com/cb040aa/webpack/peerj-app.6c...: 469 KB unused (77%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.peerj.com/cb040aa/webpack/330.a5145fec...: 65 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://peerj.com/js/8d39319-582a9a0.js: 50 KB unused (67%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://peerj.com/js/8d39319-582a9a0.js: unminified — 33 KB could be saved
Warning::
https://peerj.com/js/f67db00-8264f27.js: 46 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://peerj.com/js/f67db00-8264f27.js: unminified — 45 KB could be saved
Warning::
https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88...: 28 KB unused (34%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 684 KB
684 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js623 KB469 KB (77%)✓3rd
https://cdn.peerj.com/cb040aa/webpack/330.a5145fec.js131 KB65 KB (49%)✓3rd
https://peerj.com/js/8d39319-582a9a0.js75 KB50 KB (67%)✗1st
https://peerj.com/js/f67db00-8264f27.js94 KB46 KB (49%)✗1st
https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js84 KB28 KB (34%)✓3rd
https://cdn.mxpnl.com/libs/mixpanel-2-latest.min.js32 KB26 KB (83%)✓3rd
https://pushpad.xyz/pushpad.js6 KB—✓3rd
https://cdn.peerj.com/cb040aa/webpack/1024.3817f300.js5 KB—✓3rd
https://cdn.peerj.com/cb040aa/webpack/runtime.128817d8.js17 KB—✓3rd
https://peerj.com/js/05779bd-a411a7a.js6 KB—✗1st

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
59 resources · 2.4 MB · 684 KB savings available
FIX
59 resources · 2.4 MB · 684 KB savings available
Warning::
Page weight 1.4 MB over 1MB target
Got: 2.4 MB Expected: ≤ 1 MB
Info::
~684 KB of savings available
Warning::
45 third-party resources (90% of weight)
Info::
3 resources over 200KB
59 resources · 2.4 MiB · 45 third-party 1.4 MiB over 1MB target
JavaScript 50% · 1.2 MiB
Image 22% · 550.4 KiB
Font 18% · 433.4 KiB
CSS 8% · 187.9 KiB
Other 2% · 46.5 KiB
Document 0% · 10.1 KiB

~684.1 KiB of savings available

Remove unused JavaScript: 684.1 KiB
B
Image Optimization
4 images, 0 KB saveable
REVIEW
4 images, 0 KB saveable
Warning::
https://peerj.com/assets/images/landing-pages/peer... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://s3.amazonaws.com/static.peerj.com/images/j... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
4 images 545 KB
0 oversized -0 KB
4 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

B
HTTP Caching
max-age=0, must-revalidate, proxy-revalidate, public, s-maxage=600
REVIEW
max-age=0, must-revalidate, proxy-revalidate, public, s-maxage=600
Info::
Cache-Control header is set
Got: max-age=0, must-revalidate, proxy-revalidate, public, s-maxage=600
Info::
CDN TTL: 10 minutes (s-maxage=600)
Info::
Last-Modified header present
Cache-Control

max-age=0, must-revalidate, proxy-revalidate, public, s-maxage=600

DirectiveValueMeaning
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
proxy-revalidate—
public—Any cache may store this response
s-maxage600CDN caches for 10 minutes
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
3 fonts (433 KB)
PASS
3 fonts (433 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

433 KB total

Render-blocking

0

of 3

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 12.0 s 14.0 s 16.0 s FCP 12.1 s LCP 16.8 shttps://cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2materialdesignicons-web... https://cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2 — 284.2 KiB — 108 ms — font-display: swaphttps://fonts.gstatic.com/s/inter/v20/UcCo3FwrK3iLTcviYwYZ8UA3.woff2UcCo3FwrK3iLTcviYwYZ8UA... https://fonts.gstatic.com/s/inter/v20/UcCo3FwrK3iLTcviYwYZ8UA3.woff2 — 71.3 KiB — 81 ms — font-display: swaphttps://fonts.gstatic.com/s/inter/v20/UcCm3FwrK3iLTcvnUwQT9mI1F54.woff2UcCm3FwrK3iLTcvnUwQT9mI... https://fonts.gstatic.com/s/inter/v20/UcCm3FwrK3iLTcvnUwQT9mI1F54.woff2 — 77.9 KiB — 86 ms — font-display: swap
materialdesignicons-web... woff2 swap
Size 284 KB
Load time 108 ms
Start 745 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
UcCo3FwrK3iLTcviYwYZ8UA... woff2 swap
Size 71 KB
Load time 81 ms
Start 1.2 s
Risk FOUT — text flashes from fallback to web font
UcCm3FwrK3iLTcvnUwQT9mI... woff2 swap
Size 78 KB
Load time 86 ms
Start 1.2 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)

Fixing the unchecked items could save ~142 KB and ~284 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
6 hints, 0 missing preconnects
PASS
6 hints, 0 missing preconnects
Info::
Page uses 6 resource hint(s)

Current Resource Hints

preconnect
—
preload
—
dns-prefetch
6
prefetch
—

6 resource hints configured

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
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
59 requests over 1976ms
INFO
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s 16.0 s FCP 12.1 s LCP 16.8 shttps://peerj.com// https://peerj.com/ — 200 — 10.1 KiB — 173 ms — h2https://peerj.com/css/01fda25-aa54668.css/css/01fda25-aa54668.css https://peerj.com/css/01fda25-aa54668.css — 200 — 44.3 KiB — 465 ms — h2https://cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.csscdn.peerj.com/cb040aa/webpack/330.3... https://cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.css — 200 — 45.5 KiB — 146 ms — h2https://cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.csscdn.peerj.com/cb040aa/webpack/peerj... https://cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.css — 200 — 79.3 KiB — 165 ms — h2https://peerj.com/js/f67db00-8264f27.js/js/f67db00-8264f27.js https://peerj.com/js/f67db00-8264f27.js — 200 — 93.5 KiB — 54 ms — h2https://peerj.com/assets/js/polyfills/includes.js/assets/js/polyfills/includes.js https://peerj.com/assets/js/polyfills/includes.js — 200 — 338 B — 54 ms — h2https://peerj.com/assets/js/polyfills/startsWith.js/assets/js/polyfills/startsWith.js https://peerj.com/assets/js/polyfills/startsWith.js — 200 — 359 B — 53 ms — h2https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.jstranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.js — 200 — 77.7 KiB — 150 ms — h3https://peerj.com/js/8d39319-582a9a0.js/js/8d39319-582a9a0.js https://peerj.com/js/8d39319-582a9a0.js — 200 — 74.9 KiB — 62 ms — h2https://peerj.com/js/05779bd-a411a7a.js/js/05779bd-a411a7a.js https://peerj.com/js/05779bd-a411a7a.js — 200 — 5.8 KiB — 62 ms — h2https://cdn.peerj.com/cb040aa/webpack/runtime.128817d8.jscdn.peerj.com/cb040aa/webpack/runti... https://cdn.peerj.com/cb040aa/webpack/runtime.128817d8.js — 200 — 16.9 KiB — 143 ms — h2https://cdn.peerj.com/cb040aa/webpack/198.0671974e.jscdn.peerj.com/cb040aa/webpack/198.0... https://cdn.peerj.com/cb040aa/webpack/198.0671974e.js — 200 — 7.4 KiB — 124 ms — h2https://cdn.peerj.com/cb040aa/webpack/330.a5145fec.jscdn.peerj.com/cb040aa/webpack/330.a... https://cdn.peerj.com/cb040aa/webpack/330.a5145fec.js — 200 — 131.1 KiB — 171 ms — h2https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.jscdn.peerj.com/cb040aa/webpack/peerj... https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js — 200 — 623.1 KiB — 198 ms — h2https://fonts.googleapis.com/css2?family=Inter:ital,opsz,wght@0,14..32,100..900;1,14..32,100..900&display=swapfonts.googleapis.com/css2?family=In... https://fonts.googleapis.com/css2?family=Inter:ital,opsz,wght@0,14..32,100..900;1,14..32,100..900&display=swap — 200 — 1.1 KiB — 114 ms — h2https://peerj.com/assets/js/mixpanel.js/assets/js/mixpanel.js https://peerj.com/assets/js/mixpanel.js — 200 — 1.0 KiB — 26 ms — h2https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/policies/GDPR.jsontranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/policies/GDPR.json — 200 — 6.4 KiB — 266 ms — h3https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.jstranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js — 200 — 84.5 KiB — 326 ms — h3https://peerj.com/x-country/?_=1776899366354/x-country/?_=1776899366354 https://peerj.com/x-country/?_=1776899366354 — 200 — 418 B — 145 ms — h2https://pushpad.xyz/pushpad.jspushpad.xyz/pushpad.js https://pushpad.xyz/pushpad.js — 200 — 5.7 KiB — 108 ms — h2https://cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2cdn.peerj.com/cb040aa/webpack/fonts... https://cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2 — 200 — 284.2 KiB — 108 ms — h2https://d2pdyyx74uypu5.cloudfront.net/images/favicon/peerj/manifest.jsond2pdyyx74uypu5.cloudfront.net/image... https://d2pdyyx74uypu5.cloudfront.net/images/favicon/peerj/manifest.json — 200 — 1.8 KiB — 336 ms — http/1.1https://cdn.peerj.com/cb040aa/webpack/192.7954e175.csscdn.peerj.com/cb040aa/webpack/192.7... https://cdn.peerj.com/cb040aa/webpack/192.7954e175.css — 200 — 2.2 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/192.a4f13c83.jscdn.peerj.com/cb040aa/webpack/192.a... https://cdn.peerj.com/cb040aa/webpack/192.a4f13c83.js — 200 — 16.1 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/230.be4f9cb3.csscdn.peerj.com/cb040aa/webpack/230.b... https://cdn.peerj.com/cb040aa/webpack/230.be4f9cb3.css — 200 — 893 B — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/230.b4278b97.jscdn.peerj.com/cb040aa/webpack/230.b... https://cdn.peerj.com/cb040aa/webpack/230.b4278b97.js — 200 — 9.3 KiB — 20 ms — h2https://cdn.peerj.com/cb040aa/webpack/1024.3b00d89e.csscdn.peerj.com/cb040aa/webpack/1024.... https://cdn.peerj.com/cb040aa/webpack/1024.3b00d89e.css — 200 — 1.0 KiB — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/1024.3817f300.jscdn.peerj.com/cb040aa/webpack/1024.... https://cdn.peerj.com/cb040aa/webpack/1024.3817f300.js — 200 — 4.8 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/1040.251e73b2.csscdn.peerj.com/cb040aa/webpack/1040.... https://cdn.peerj.com/cb040aa/webpack/1040.251e73b2.css — 200 — 407 B — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/1040.6aab3c12.jscdn.peerj.com/cb040aa/webpack/1040.... https://cdn.peerj.com/cb040aa/webpack/1040.6aab3c12.js — 200 — 2.0 KiB — 19 ms — h2
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s 16.0 s FCP 12.1 s LCP 16.8 shttps://peerj.com// https://peerj.com/ — 200 — 10.1 KiB — 173 ms — h2https://peerj.com/css/01fda25-aa54668.css/css/01fda25-aa54668.css https://peerj.com/css/01fda25-aa54668.css — 200 — 44.3 KiB — 465 ms — h2https://cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.csscdn.peerj.com/cb040aa/webpack/330.3... https://cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.css — 200 — 45.5 KiB — 146 ms — h2https://cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.csscdn.peerj.com/cb040aa/webpack/peerj... https://cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.css — 200 — 79.3 KiB — 165 ms — h2https://peerj.com/js/f67db00-8264f27.js/js/f67db00-8264f27.js https://peerj.com/js/f67db00-8264f27.js — 200 — 93.5 KiB — 54 ms — h2https://peerj.com/assets/js/polyfills/includes.js/assets/js/polyfills/includes.js https://peerj.com/assets/js/polyfills/includes.js — 200 — 338 B — 54 ms — h2https://peerj.com/assets/js/polyfills/startsWith.js/assets/js/polyfills/startsWith.js https://peerj.com/assets/js/polyfills/startsWith.js — 200 — 359 B — 53 ms — h2https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.jstranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.js — 200 — 77.7 KiB — 150 ms — h3https://peerj.com/js/8d39319-582a9a0.js/js/8d39319-582a9a0.js https://peerj.com/js/8d39319-582a9a0.js — 200 — 74.9 KiB — 62 ms — h2https://peerj.com/js/05779bd-a411a7a.js/js/05779bd-a411a7a.js https://peerj.com/js/05779bd-a411a7a.js — 200 — 5.8 KiB — 62 ms — h2https://cdn.peerj.com/cb040aa/webpack/runtime.128817d8.jscdn.peerj.com/cb040aa/webpack/runti... https://cdn.peerj.com/cb040aa/webpack/runtime.128817d8.js — 200 — 16.9 KiB — 143 ms — h2https://cdn.peerj.com/cb040aa/webpack/198.0671974e.jscdn.peerj.com/cb040aa/webpack/198.0... https://cdn.peerj.com/cb040aa/webpack/198.0671974e.js — 200 — 7.4 KiB — 124 ms — h2https://cdn.peerj.com/cb040aa/webpack/330.a5145fec.jscdn.peerj.com/cb040aa/webpack/330.a... https://cdn.peerj.com/cb040aa/webpack/330.a5145fec.js — 200 — 131.1 KiB — 171 ms — h2https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.jscdn.peerj.com/cb040aa/webpack/peerj... https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js — 200 — 623.1 KiB — 198 ms — h2https://fonts.googleapis.com/css2?family=Inter:ital,opsz,wght@0,14..32,100..900;1,14..32,100..900&display=swapfonts.googleapis.com/css2?family=In... https://fonts.googleapis.com/css2?family=Inter:ital,opsz,wght@0,14..32,100..900;1,14..32,100..900&display=swap — 200 — 1.1 KiB — 114 ms — h2https://peerj.com/assets/js/mixpanel.js/assets/js/mixpanel.js https://peerj.com/assets/js/mixpanel.js — 200 — 1.0 KiB — 26 ms — h2https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/policies/GDPR.jsontranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/policies/GDPR.json — 200 — 6.4 KiB — 266 ms — h3https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.jstranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js — 200 — 84.5 KiB — 326 ms — h3https://peerj.com/x-country/?_=1776899366354/x-country/?_=1776899366354 https://peerj.com/x-country/?_=1776899366354 — 200 — 418 B — 145 ms — h2https://pushpad.xyz/pushpad.jspushpad.xyz/pushpad.js https://pushpad.xyz/pushpad.js — 200 — 5.7 KiB — 108 ms — h2https://cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2cdn.peerj.com/cb040aa/webpack/fonts... https://cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2 — 200 — 284.2 KiB — 108 ms — h2https://d2pdyyx74uypu5.cloudfront.net/images/favicon/peerj/manifest.jsond2pdyyx74uypu5.cloudfront.net/image... https://d2pdyyx74uypu5.cloudfront.net/images/favicon/peerj/manifest.json — 200 — 1.8 KiB — 336 ms — http/1.1https://cdn.peerj.com/cb040aa/webpack/192.7954e175.csscdn.peerj.com/cb040aa/webpack/192.7... https://cdn.peerj.com/cb040aa/webpack/192.7954e175.css — 200 — 2.2 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/192.a4f13c83.jscdn.peerj.com/cb040aa/webpack/192.a... https://cdn.peerj.com/cb040aa/webpack/192.a4f13c83.js — 200 — 16.1 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/230.be4f9cb3.csscdn.peerj.com/cb040aa/webpack/230.b... https://cdn.peerj.com/cb040aa/webpack/230.be4f9cb3.css — 200 — 893 B — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/230.b4278b97.jscdn.peerj.com/cb040aa/webpack/230.b... https://cdn.peerj.com/cb040aa/webpack/230.b4278b97.js — 200 — 9.3 KiB — 20 ms — h2https://cdn.peerj.com/cb040aa/webpack/1024.3b00d89e.csscdn.peerj.com/cb040aa/webpack/1024.... https://cdn.peerj.com/cb040aa/webpack/1024.3b00d89e.css — 200 — 1.0 KiB — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/1024.3817f300.jscdn.peerj.com/cb040aa/webpack/1024.... https://cdn.peerj.com/cb040aa/webpack/1024.3817f300.js — 200 — 4.8 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/1040.251e73b2.csscdn.peerj.com/cb040aa/webpack/1040.... https://cdn.peerj.com/cb040aa/webpack/1040.251e73b2.css — 200 — 407 B — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/1040.6aab3c12.jscdn.peerj.com/cb040aa/webpack/1040.... https://cdn.peerj.com/cb040aa/webpack/1040.6aab3c12.js — 200 — 2.0 KiB — 19 ms — h2https://cdn.mxpnl.com/libs/mixpanel-2-latest.min.jscdn.mxpnl.com/libs/mixpanel-2-lates... https://cdn.mxpnl.com/libs/mixpanel-2-latest.min.js — 200 — 31.7 KiB — 121 ms — h2https://peerj.com/event/iprange/?_=1776899366355/event/iprange/?_=1776899366355 https://peerj.com/event/iprange/?_=1776899366355 — 200 — 105 B — 153 ms — h2https://cdn.peerj.com/cb040aa/webpack/0.4a8639c8.csscdn.peerj.com/cb040aa/webpack/0.4a8... https://cdn.peerj.com/cb040aa/webpack/0.4a8639c8.css — 200 — 2.0 KiB — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/0.447f5e85.jscdn.peerj.com/cb040aa/webpack/0.447... https://cdn.peerj.com/cb040aa/webpack/0.447f5e85.js — 200 — 3.9 KiB — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/1021.b4db90eb.csscdn.peerj.com/cb040aa/webpack/1021.... https://cdn.peerj.com/cb040aa/webpack/1021.b4db90eb.css — 200 — 3.3 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/1021.178998b7.jscdn.peerj.com/cb040aa/webpack/1021.... https://cdn.peerj.com/cb040aa/webpack/1021.178998b7.js — 200 — 5.2 KiB — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/66.58de92c7.csscdn.peerj.com/cb040aa/webpack/66.58... https://cdn.peerj.com/cb040aa/webpack/66.58de92c7.css — 200 — 627 B — 20 ms — h2https://cdn.peerj.com/cb040aa/webpack/66.1d672afc.jscdn.peerj.com/cb040aa/webpack/66.1d... https://cdn.peerj.com/cb040aa/webpack/66.1d672afc.js — 200 — 6.0 KiB — 18 ms — h2https://cdn.peerj.com/cb040aa/webpack/253.45f7f44a.csscdn.peerj.com/cb040aa/webpack/253.4... https://cdn.peerj.com/cb040aa/webpack/253.45f7f44a.css — 200 — 577 B — 19 ms — h2https://cdn.peerj.com/cb040aa/webpack/253.a14f93c1.jscdn.peerj.com/cb040aa/webpack/253.a... https://cdn.peerj.com/cb040aa/webpack/253.a14f93c1.js — 200 — 7.8 KiB — 20 ms — h2https://cdn.peerj.com/cb040aa/webpack/1009.ac3a2b66.csscdn.peerj.com/cb040aa/webpack/1009.... https://cdn.peerj.com/cb040aa/webpack/1009.ac3a2b66.css — 200 — 1.7 KiB — 21 ms — h2https://cdn.peerj.com/cb040aa/webpack/1009.ce1d475f.jscdn.peerj.com/cb040aa/webpack/1009.... https://cdn.peerj.com/cb040aa/webpack/1009.ce1d475f.js — 200 — 24.4 KiB — 25 ms — h2https://cdn.peerj.com/cb040aa/webpack/1042.678cac5e.csscdn.peerj.com/cb040aa/webpack/1042.... https://cdn.peerj.com/cb040aa/webpack/1042.678cac5e.css — 200 — 586 B — 22 ms — h2https://cdn.peerj.com/cb040aa/webpack/1042.5ccb8502.jscdn.peerj.com/cb040aa/webpack/1042.... https://cdn.peerj.com/cb040aa/webpack/1042.5ccb8502.js — 200 — 2.2 KiB — 22 ms — h2https://cdn.peerj.com/cb040aa/webpack/398.02ed4a60.csscdn.peerj.com/cb040aa/webpack/398.0... https://cdn.peerj.com/cb040aa/webpack/398.02ed4a60.css — 200 — 965 B — 20 ms — h2https://cdn.peerj.com/cb040aa/webpack/398.8481fb5e.jscdn.peerj.com/cb040aa/webpack/398.8... https://cdn.peerj.com/cb040aa/webpack/398.8481fb5e.js — 200 — 5.8 KiB — 18 ms — h2https://peerj.com/api/v2/groups?hub=true/api/v2/groups?hub=true https://peerj.com/api/v2/groups?hub=true — 200 — 3.9 KiB — 181 ms — h2https://peerj.com/assets/images/landing-pages/peerj-bio-logo.svg/assets/images/landing-pages/peerj-... https://peerj.com/assets/images/landing-pages/peerj-bio-logo.svg — 200 — 1.5 KiB — 45 ms — h2https://s3.amazonaws.com/static.peerj.com/images/journal-home/logos/logo-journal-cs.svgs3.amazonaws.com/static.peerj.com/i... https://s3.amazonaws.com/static.peerj.com/images/journal-home/logos/logo-journal-cs.svg — 200 — 22.1 KiB — 355 ms — http/1.1https://peerj.com/blog-feed.json/blog-feed.json https://peerj.com/blog-feed.json — 200 — 16.0 KiB — 820 ms — h2https://fonts.gstatic.com/s/inter/v20/UcCo3FwrK3iLTcviYwYZ8UA3.woff2fonts.gstatic.com/s/inter/v20/UcCo3... https://fonts.gstatic.com/s/inter/v20/UcCo3FwrK3iLTcviYwYZ8UA3.woff2 — 200 — 71.3 KiB — 81 ms — h3https://fonts.gstatic.com/s/inter/v20/UcCm3FwrK3iLTcvnUwQT9mI1F54.woff2fonts.gstatic.com/s/inter/v20/UcCm3... https://fonts.gstatic.com/s/inter/v20/UcCm3FwrK3iLTcvnUwQT9mI1F54.woff2 — 200 — 77.9 KiB — 86 ms — h3https://peerj.com/api/v2/groups?hub=true/api/v2/groups?hub=true https://peerj.com/api/v2/groups?hub=true — 200 — 191 B — 189 ms — h2https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/vendor-list.jsontranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/vendor-list.json — 200 — 15.5 KiB — 307 ms — h3https://d2pdyyx74uypu5.cloudfront.net/images/home/PeerJHomepageSplash-1908x450.jpgd2pdyyx74uypu5.cloudfront.net/image... https://d2pdyyx74uypu5.cloudfront.net/images/home/PeerJHomepageSplash-1908x450.jpg — 200 — 139.5 KiB — 88 ms — http/1.1https://d2pdyyx74uypu5.cloudfront.net/images/journal-home/headers/PeerJ-Journal-Home-950w.jpgd2pdyyx74uypu5.cloudfront.net/image... https://d2pdyyx74uypu5.cloudfront.net/images/journal-home/headers/PeerJ-Journal-Home-950w.jpg — 200 — 381.5 KiB — 113 ms — http/1.1https://d2pdyyx74uypu5.cloudfront.net/images/favicon/peerj/favicon.icod2pdyyx74uypu5.cloudfront.net/image... https://d2pdyyx74uypu5.cloudfront.net/images/favicon/peerj/favicon.ico — 200 — 5.9 KiB — 307 ms — http/1.1https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/translations/en.jsontranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/translations/en.json — 200 — 2.2 KiB — 275 ms — h3https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/tcf.csstranscend-cdn.com/cm/ef49a3f1-d8c1-... https://transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/tcf.css — 200 — 3.4 KiB — 34 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
87% of JavaScript execution is third-party
First-party Third-party 3009ms · 958KB · €33/mo
cdn.peerj.com
Other
Costly
Execution 858ms
Transfer 623 KB
Unused 77%
Monthly Cost €9/mo
cdn.peerj.com
Other
Costly
Execution 604ms
Transfer 2 KB
Monthly Cost €7/mo
Unattributable
Other
Costly
Execution 338ms
Transfer 0 KB
Monthly Cost €4/mo
cdn.peerj.com
Other
Costly
Execution 324ms
Transfer 24 KB
Monthly Cost €4/mo
cdn.peerj.com
Other
Costly
Execution 297ms
Transfer 6 KB
Monthly Cost €3/mo
transcend-cdn.com
Other
Costly
Execution 201ms
Transfer 84 KB
Unused 34%
Monthly Cost €2/mo
transcend-cdn.com
Other
Optional
Execution 181ms
Transfer 78 KB
Monthly Cost €2/mo
cdn.peerj.com
Other
Optional
Execution 140ms
Transfer 131 KB
Unused 49%
Monthly Cost €2/mo
cdn.peerj.com
Other
Optional
Execution 67ms
Transfer 9 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • cdn.peerj.com adds 858ms and costs ~€9/month
  • cdn.peerj.com adds 604ms and costs ~€7/month
  • Unattributable adds 338ms and costs ~€4/month
  • cdn.peerj.com adds 324ms and costs ~€4/month
  • cdn.peerj.com adds 297ms and costs ~€3/month
  • transcend-cdn.com adds 201ms and costs ~€2/month

87% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

cdn.peerj.com takes 858ms 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

77% of cdn.peerj.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

cdn.peerj.com takes 604ms 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

Unattributable takes 338ms 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.peerj.com takes 324ms 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.peerj.com takes 297ms 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

transcend-cdn.com takes 201ms 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

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