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Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
67
GRADE
D
FIX
5
REVIEW
3
PASS
5
INFO
2

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

Mobile Desktop
61
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
71
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
85
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.

2.23 s

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

4.16 s

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

0 ms

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

0.107

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

2.88 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.

4.16 s

Page Load Progression

566 ms
1.1 s
1.7 s
2.3 s
2.8 s
3.4 s
4.0 s
4.5 s
Checks
15
5 PASS 3 REVIEW 5 FIX
F
Page Weight Budget
Action
4.3 MB transferred, 44 requests
FIX
4.3 MB transferred, 44 requests
Critical::
Page weighs 8.3 MB (4.3 MB transferred)
Warning::
JavaScript is 2.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.8 MB
Info::
Fonts are 1.1 MB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 1.1 MB
Info::
CSS is 267 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 267 KB
Info::
44 HTTP requests
Info::
Estimated 0.89 g CO2 per page load
4.3 MB / 2.4 MB budget
4.3 MB transferred
44 requests
0.89 g CO2 per page load
JavaScript 2.8 MiB 65%
Fonts 1.1 MiB 26%
CSS 267.2 KiB 6%
Images 44.1 KiB 1%
Other 37.1 KiB 1%
HTML 33.8 KiB 1%
Other 8.1 KiB 0%
0 2.4 MB 4.9 MB
Over budget

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

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Why this matters

CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.

Source: web.dev

D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (4.3 MiB of 4.3 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Bundles
Action
14 scripts, 2.0 MB unused
FIX
14 scripts, 2.0 MB unused
Warning::
https://www.uptodate.com/app/dist/utd-all-BtFJPR2f...: 967 KB unused (73%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.uptodate.com/app/dist/vendor-DMdb3ILA....: 382 KB unused (56%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.gstatic.com/recaptcha/releases/gTpTIWh...: 177 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.gstatic.com/recaptcha/releases/gTpTIWh...: 177 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.gstatic.com/recaptcha/releases/gTpTIWh...: 177 KB unused (49%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 2.0 MB
2056 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.uptodate.com/app/dist/utd-all-BtFJPR2f.min.js1319 KB967 KB (73%)✓3rd
https://www.uptodate.com/app/dist/vendor-DMdb3ILA.min.js679 KB382 KB (56%)✓3rd
https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js362 KB177 KB (49%)✓3rd
https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js0 KB177 KB (49%)✓3rd
https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js0 KB177 KB (49%)✓3rd
https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js362 KB177 KB (49%)✓3rd
https://www.uptodate.com/app/dist/index-CEWs5uCT.min.js3 KB—✓3rd
https://www.uptodate.com/app/dist/pace-B_2Z1FtK.min.js16 KB—✓3rd
https://cdn.cookielaw.org/consent/560a8aa4-c54c-486f-9bc4-35a3f22bacd9/OtAutoBlock.js0 KB—✓3rd
https://cdn.cookielaw.org/scripttemplates/otSDKStub.js0 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
44 resources · 4.3 MB · 2.0 MB savings available
FIX
44 resources · 4.3 MB · 2.0 MB savings available
Warning::
Page weight 3.3 MB over 1MB target
Got: 4.3 MB Expected: ≤ 1 MB
Info::
~2.0 MB of savings available
Warning::
43 third-party resources (100% of weight)
Info::
5 resources over 200KB
44 resources · 4.3 MiB · 43 third-party 3.3 MiB over 1MB target
JavaScript 65% · 2.8 MiB
Font 26% · 1.1 MiB
CSS 6% · 267.2 KiB
Image 1% · 48.8 KiB
Other 1% · 39.4 KiB
Document 1% · 34.9 KiB

~2.0 MiB of savings available

Remove unused JavaScript: 2.0 MiB
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
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Warning::
https://cdn.wolterskluwer.io/wk-logos/1.0.x/wk-bra... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.uptodate.com/app/utd-menu/utd-logo.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
7 images 44 KB
0 oversized -0 KB
7 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
JS Execution Cost
565ms total JS execution
REVIEW
565ms total JS execution
Info::
https://www.uptodate.com/app/dist/pace-B_2Z1FtK.mi...: 174ms CPU time
Info::
Unattributable: 155ms CPU time
Info::
https://www.gstatic.com/recaptcha/releases/gTpTIWh...: 151ms CPU time
Info::
https://www.uptodate.com/login: 86ms CPU time
Warning::
Third-party scripts: 565ms (100% of total)

Main Thread Breakdown

Script Evaluation 52% Other 23% Style & Layout 14% Script Parsing & Compilation 3%
ScriptTotalScriptingParse/CompileParty
https://www.uptodate.com/app/dist/pace-B_2Z1FtK.min.js174ms141ms0ms3rd
Unattributable155ms37ms0ms3rd
https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js151ms129ms18ms3rd
https://www.uptodate.com/login86ms1ms0ms3rd
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

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
8 fonts (1129 KB)
PASS
8 fonts (1129 KB)
Info::
8 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

8

1129 KB total

Render-blocking

0

of 8

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 2.2 s LCP 4.2 shttps://www.uptodate.com/app/assets/NotoSans-Regular-CUnezwo1.woff2NotoSans-Regular-CUnezw... https://www.uptodate.com/app/assets/NotoSans-Regular-CUnezwo1.woff2 — 165.3 KiB — 66 ms — font-display: swaphttps://www.uptodate.com/app/assets/NotoSans-Bold-CjI8rmzb.woff2NotoSans-Bold-CjI8rmzb.... https://www.uptodate.com/app/assets/NotoSans-Bold-CjI8rmzb.woff2 — 163.4 KiB — 99 ms — font-display: swaphttps://www.uptodate.com/app/assets/wk-icons-8dBf3Vus.woff2wk-icons-8dBf3Vus.woff2 https://www.uptodate.com/app/assets/wk-icons-8dBf3Vus.woff2 — 34.9 KiB — 41 ms — font-display: swaphttps://www.uptodate.com/app/assets/NotoSans-SemiBold-eeohmkRK.woff2NotoSans-SemiBold-eeohm... https://www.uptodate.com/app/assets/NotoSans-SemiBold-eeohmkRK.woff2 — 167.9 KiB — 190 ms — font-display: swaphttps://www.uptodate.com/app/assets/NotoSans-Light-DzqmUfbq.woff2NotoSans-Light-DzqmUfbq... https://www.uptodate.com/app/assets/NotoSans-Light-DzqmUfbq.woff2 — 164.8 KiB — 102 ms — font-display: swaphttps://www.uptodate.com/app/assets/wk-icons-open-I9AnqcVf.woffwk-icons-open-I9AnqcVf.... https://www.uptodate.com/app/assets/wk-icons-open-I9AnqcVf.woff — 71.2 KiB — 70 ms — font-display: swaphttps://www.uptodate.com/app/assets/FiraSans-Regular-BTnMGPMZ.woffFiraSans-Regular-BTnMGP... https://www.uptodate.com/app/assets/FiraSans-Regular-BTnMGPMZ.woff — 180.9 KiB — 71 ms — font-display: swaphttps://www.uptodate.com/app/assets/FiraSans-Light-CcuDwDV2.woffFiraSans-Light-CcuDwDV2... https://www.uptodate.com/app/assets/FiraSans-Light-CcuDwDV2.woff — 180.6 KiB — 69 ms — font-display: swap
NotoSans-Regular-CUnezw... woff2 swap
Size 165 KB
Load time 66 ms
Start 1.4 s
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
NotoSans-Bold-CjI8rmzb.... woff2 swap
Size 163 KB
Load time 99 ms
Start 1.5 s
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
wk-icons-8dBf3Vus.woff2 woff2 swap
Size 35 KB
Load time 41 ms
Start 1.5 s
Risk FOUT — text flashes from fallback to web font
NotoSans-SemiBold-eeohm... woff2 swap
Size 168 KB
Load time 190 ms
Start 1.5 s
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
NotoSans-Light-DzqmUfbq... woff2 swap
Size 165 KB
Load time 102 ms
Start 1.5 s
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
wk-icons-open-I9AnqcVf.... woff swap
Size 71 KB
Load time 70 ms
Start 1.5 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
FiraSans-Regular-BTnMGP... woff swap
Size 181 KB
Load time 71 ms
Start 1.5 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
FiraSans-Light-CcuDwDV2... woff swap
Size 181 KB
Load time 69 ms
Start 1.6 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~641 KB and ~1282 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
Network Waterfall
44 requests over 3339ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 2.2 s LCP 4.2 shttps://uptodate.com// https://uptodate.com/ — 301 — 555 B — 540 ms — http/1.1https://www.uptodate.com/www.uptodate.com/ https://www.uptodate.com/ — 301 — 560 B — 107 ms — http/1.1https://www.uptodate.com/indexwww.uptodate.com/index https://www.uptodate.com/index — 302 — 2.3 KiB — 77 ms — http/1.1https://www.uptodate.com/loginwww.uptodate.com/login https://www.uptodate.com/login — 200 — 3.9 KiB — 37 ms — http/1.1https://www.google.com/recaptcha/enterprise.js?render=explicitwww.google.com/recaptcha/enterprise... https://www.google.com/recaptcha/enterprise.js?render=explicit — 200 — 1.0 KiB — 63 ms — h3https://www.uptodate.com/app/dist/DOM-Cws02s0j.min.jswww.uptodate.com/app/dist/DOM-Cws02... https://www.uptodate.com/app/dist/DOM-Cws02s0j.min.js — 200 — 88.1 KiB — 70 ms — http/1.1https://www.uptodate.com/app/dist/epic-ClRhenuO.min.jswww.uptodate.com/app/dist/epic-ClRh... https://www.uptodate.com/app/dist/epic-ClRhenuO.min.js — 200 — 3.5 KiB — 104 ms — http/1.1https://www.uptodate.com/app/assets/utd-all-C4EXBBMH.csswww.uptodate.com/app/assets/utd-all... https://www.uptodate.com/app/assets/utd-all-C4EXBBMH.css — 200 — 218.8 KiB — 204 ms — http/1.1https://www.uptodate.com/app/dist/index-CEWs5uCT.min.jswww.uptodate.com/app/dist/index-CEW... https://www.uptodate.com/app/dist/index-CEWs5uCT.min.js — 200 — 2.8 KiB — 107 ms — http/1.1https://www.uptodate.com/app/dist/vendor-DMdb3ILA.min.jswww.uptodate.com/app/dist/vendor-DM... https://www.uptodate.com/app/dist/vendor-DMdb3ILA.min.js — 200 — 679.3 KiB — 291 ms — http/1.1https://www.uptodate.com/app/dist/utd-all-BtFJPR2f.min.jswww.uptodate.com/app/dist/utd-all-B... https://www.uptodate.com/app/dist/utd-all-BtFJPR2f.min.js — 200 — 1.3 MiB — 474 ms — http/1.1https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.jswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js — 200 — 362.4 KiB — 165 ms — h2https://www.uptodate.com/app/utd-menu/utd-icon.pngwww.uptodate.com/app/utd-menu/utd-i... https://www.uptodate.com/app/utd-menu/utd-icon.png — 200 — 2.2 KiB — 38 ms — http/1.1https://www.uptodate.com/app/dist/pace-B_2Z1FtK.min.jswww.uptodate.com/app/dist/pace-B_2Z... https://www.uptodate.com/app/dist/pace-B_2Z1FtK.min.js — 200 — 15.6 KiB — 37 ms — http/1.1https://www.uptodate.com/app/utd-menu/utd-icon-redesign.pngwww.uptodate.com/app/utd-menu/utd-i... https://www.uptodate.com/app/utd-menu/utd-icon-redesign.png — 200 — 4.7 KiB — 36 ms — http/1.1https://www.uptodate.com/services/app/init/json?id=YXBwQ29udGFpbmVywww.uptodate.com/services/app/init/... https://www.uptodate.com/services/app/init/json?id=YXBwQ29udGFpbmVy — 200 — 9.6 KiB — 43 ms — http/1.1https://www.uptodate.com/app/utd-menu/wk-wheel-icon.svgwww.uptodate.com/app/utd-menu/wk-wh... https://www.uptodate.com/app/utd-menu/wk-wheel-icon.svg — 200 — 4.3 KiB — 41 ms — http/1.1https://www.uptodate.com/app/utd-menu/utd-logo.svgwww.uptodate.com/app/utd-menu/utd-l... https://www.uptodate.com/app/utd-menu/utd-logo.svg — 200 — 8.3 KiB — 41 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-Regular-CUnezwo1.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-Regular-CUnezwo1.woff2 — 200 — 165.3 KiB — 66 ms — http/1.1https://www.uptodate.com/app/assets/WK-Logo-7lXiX5v8.svgwww.uptodate.com/app/assets/WK-Logo... https://www.uptodate.com/app/assets/WK-Logo-7lXiX5v8.svg — 200 — 9.9 KiB — 39 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-Bold-CjI8rmzb.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-Bold-CjI8rmzb.woff2 — 200 — 163.4 KiB — 99 ms — http/1.1https://www.uptodate.com/app/assets/wk-icons-8dBf3Vus.woff2www.uptodate.com/app/assets/wk-icon... https://www.uptodate.com/app/assets/wk-icons-8dBf3Vus.woff2 — 200 — 34.9 KiB — 41 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-SemiBold-eeohmkRK.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-SemiBold-eeohmkRK.woff2 — 200 — 167.9 KiB — 190 ms — http/1.1https://www.uptodate.com/services/app/localization/file?lang=frwww.uptodate.com/services/app/local... https://www.uptodate.com/services/app/localization/file?lang=fr — 200 — 23.3 KiB — 41 ms — http/1.1https://www.uptodate.com/services/app/event/login/json?source=login-subscribe-view&isCaptchaSectionVisible=falsewww.uptodate.com/services/app/event... https://www.uptodate.com/services/app/event/login/json?source=login-subscribe-view&isCaptchaSectionVisible=false — 204 — 1.7 KiB — 39 ms — http/1.1https://www.uptodate.com/services/app/config/footer/jsonwww.uptodate.com/services/app/confi... https://www.uptodate.com/services/app/config/footer/json — 200 — 2.5 KiB — 62 ms — http/1.1https://www.uptodate.com/contents/assets/css/UTD_gx_gen.csswww.uptodate.com/contents/assets/cs... https://www.uptodate.com/contents/assets/css/UTD_gx_gen.css — 200 — 6.7 KiB — 62 ms — http/1.1https://cdn.cookielaw.org/consent/560a8aa4-c54c-486f-9bc4-35a3f22bacd9/OtAutoBlock.jscdn.cookielaw.org/consent/560a8aa4-... https://cdn.cookielaw.org/consent/560a8aa4-c54c-486f-9bc4-35a3f22bacd9/OtAutoBlock.js — -1 — 0 B — 81 ms — https://cdn.cookielaw.org/scripttemplates/otSDKStub.jscdn.cookielaw.org/scripttemplates/o... https://cdn.cookielaw.org/scripttemplates/otSDKStub.js — -1 — 0 B — 81 ms — https://www.uptodate.com/app/assets/open-athens-logo-purple-Dep7k9zT.svgwww.uptodate.com/app/assets/open-at... https://www.uptodate.com/app/assets/open-athens-logo-purple-Dep7k9zT.svg — 200 — 6.8 KiB — 39 ms — http/1.1
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 2.2 s LCP 4.2 shttps://uptodate.com// https://uptodate.com/ — 301 — 555 B — 540 ms — http/1.1https://www.uptodate.com/www.uptodate.com/ https://www.uptodate.com/ — 301 — 560 B — 107 ms — http/1.1https://www.uptodate.com/indexwww.uptodate.com/index https://www.uptodate.com/index — 302 — 2.3 KiB — 77 ms — http/1.1https://www.uptodate.com/loginwww.uptodate.com/login https://www.uptodate.com/login — 200 — 3.9 KiB — 37 ms — http/1.1https://www.google.com/recaptcha/enterprise.js?render=explicitwww.google.com/recaptcha/enterprise... https://www.google.com/recaptcha/enterprise.js?render=explicit — 200 — 1.0 KiB — 63 ms — h3https://www.uptodate.com/app/dist/DOM-Cws02s0j.min.jswww.uptodate.com/app/dist/DOM-Cws02... https://www.uptodate.com/app/dist/DOM-Cws02s0j.min.js — 200 — 88.1 KiB — 70 ms — http/1.1https://www.uptodate.com/app/dist/epic-ClRhenuO.min.jswww.uptodate.com/app/dist/epic-ClRh... https://www.uptodate.com/app/dist/epic-ClRhenuO.min.js — 200 — 3.5 KiB — 104 ms — http/1.1https://www.uptodate.com/app/assets/utd-all-C4EXBBMH.csswww.uptodate.com/app/assets/utd-all... https://www.uptodate.com/app/assets/utd-all-C4EXBBMH.css — 200 — 218.8 KiB — 204 ms — http/1.1https://www.uptodate.com/app/dist/index-CEWs5uCT.min.jswww.uptodate.com/app/dist/index-CEW... https://www.uptodate.com/app/dist/index-CEWs5uCT.min.js — 200 — 2.8 KiB — 107 ms — http/1.1https://www.uptodate.com/app/dist/vendor-DMdb3ILA.min.jswww.uptodate.com/app/dist/vendor-DM... https://www.uptodate.com/app/dist/vendor-DMdb3ILA.min.js — 200 — 679.3 KiB — 291 ms — http/1.1https://www.uptodate.com/app/dist/utd-all-BtFJPR2f.min.jswww.uptodate.com/app/dist/utd-all-B... https://www.uptodate.com/app/dist/utd-all-BtFJPR2f.min.js — 200 — 1.3 MiB — 474 ms — http/1.1https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.jswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js — 200 — 362.4 KiB — 165 ms — h2https://www.uptodate.com/app/utd-menu/utd-icon.pngwww.uptodate.com/app/utd-menu/utd-i... https://www.uptodate.com/app/utd-menu/utd-icon.png — 200 — 2.2 KiB — 38 ms — http/1.1https://www.uptodate.com/app/dist/pace-B_2Z1FtK.min.jswww.uptodate.com/app/dist/pace-B_2Z... https://www.uptodate.com/app/dist/pace-B_2Z1FtK.min.js — 200 — 15.6 KiB — 37 ms — http/1.1https://www.uptodate.com/app/utd-menu/utd-icon-redesign.pngwww.uptodate.com/app/utd-menu/utd-i... https://www.uptodate.com/app/utd-menu/utd-icon-redesign.png — 200 — 4.7 KiB — 36 ms — http/1.1https://www.uptodate.com/services/app/init/json?id=YXBwQ29udGFpbmVywww.uptodate.com/services/app/init/... https://www.uptodate.com/services/app/init/json?id=YXBwQ29udGFpbmVy — 200 — 9.6 KiB — 43 ms — http/1.1https://www.uptodate.com/app/utd-menu/wk-wheel-icon.svgwww.uptodate.com/app/utd-menu/wk-wh... https://www.uptodate.com/app/utd-menu/wk-wheel-icon.svg — 200 — 4.3 KiB — 41 ms — http/1.1https://www.uptodate.com/app/utd-menu/utd-logo.svgwww.uptodate.com/app/utd-menu/utd-l... https://www.uptodate.com/app/utd-menu/utd-logo.svg — 200 — 8.3 KiB — 41 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-Regular-CUnezwo1.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-Regular-CUnezwo1.woff2 — 200 — 165.3 KiB — 66 ms — http/1.1https://www.uptodate.com/app/assets/WK-Logo-7lXiX5v8.svgwww.uptodate.com/app/assets/WK-Logo... https://www.uptodate.com/app/assets/WK-Logo-7lXiX5v8.svg — 200 — 9.9 KiB — 39 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-Bold-CjI8rmzb.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-Bold-CjI8rmzb.woff2 — 200 — 163.4 KiB — 99 ms — http/1.1https://www.uptodate.com/app/assets/wk-icons-8dBf3Vus.woff2www.uptodate.com/app/assets/wk-icon... https://www.uptodate.com/app/assets/wk-icons-8dBf3Vus.woff2 — 200 — 34.9 KiB — 41 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-SemiBold-eeohmkRK.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-SemiBold-eeohmkRK.woff2 — 200 — 167.9 KiB — 190 ms — http/1.1https://www.uptodate.com/services/app/localization/file?lang=frwww.uptodate.com/services/app/local... https://www.uptodate.com/services/app/localization/file?lang=fr — 200 — 23.3 KiB — 41 ms — http/1.1https://www.uptodate.com/services/app/event/login/json?source=login-subscribe-view&isCaptchaSectionVisible=falsewww.uptodate.com/services/app/event... https://www.uptodate.com/services/app/event/login/json?source=login-subscribe-view&isCaptchaSectionVisible=false — 204 — 1.7 KiB — 39 ms — http/1.1https://www.uptodate.com/services/app/config/footer/jsonwww.uptodate.com/services/app/confi... https://www.uptodate.com/services/app/config/footer/json — 200 — 2.5 KiB — 62 ms — http/1.1https://www.uptodate.com/contents/assets/css/UTD_gx_gen.csswww.uptodate.com/contents/assets/cs... https://www.uptodate.com/contents/assets/css/UTD_gx_gen.css — 200 — 6.7 KiB — 62 ms — http/1.1https://cdn.cookielaw.org/consent/560a8aa4-c54c-486f-9bc4-35a3f22bacd9/OtAutoBlock.jscdn.cookielaw.org/consent/560a8aa4-... https://cdn.cookielaw.org/consent/560a8aa4-c54c-486f-9bc4-35a3f22bacd9/OtAutoBlock.js — -1 — 0 B — 81 ms — https://cdn.cookielaw.org/scripttemplates/otSDKStub.jscdn.cookielaw.org/scripttemplates/o... https://cdn.cookielaw.org/scripttemplates/otSDKStub.js — -1 — 0 B — 81 ms — https://www.uptodate.com/app/assets/open-athens-logo-purple-Dep7k9zT.svgwww.uptodate.com/app/assets/open-at... https://www.uptodate.com/app/assets/open-athens-logo-purple-Dep7k9zT.svg — 200 — 6.8 KiB — 39 ms — http/1.1https://www.uptodate.com/app/assets/microsoft-logo-blue-BeURMre4.svgwww.uptodate.com/app/assets/microso... https://www.uptodate.com/app/assets/microsoft-logo-blue-BeURMre4.svg — 200 — 10.0 KiB — 83 ms — http/1.1https://www.uptodate.com/app/assets/NotoSans-Light-DzqmUfbq.woff2www.uptodate.com/app/assets/NotoSan... https://www.uptodate.com/app/assets/NotoSans-Light-DzqmUfbq.woff2 — 200 — 164.8 KiB — 102 ms — http/1.1https://www.uptodate.com/app/assets/wk-icons-open-I9AnqcVf.woffwww.uptodate.com/app/assets/wk-icon... https://www.uptodate.com/app/assets/wk-icons-open-I9AnqcVf.woff — 200 — 71.2 KiB — 70 ms — http/1.1https://www.uptodate.com/app/assets/FiraSans-Regular-BTnMGPMZ.woffwww.uptodate.com/app/assets/FiraSan... https://www.uptodate.com/app/assets/FiraSans-Regular-BTnMGPMZ.woff — 200 — 180.9 KiB — 71 ms — http/1.1https://cdn.wolterskluwer.io/wk-logos/1.0.x/wk-brand-white.svgcdn.wolterskluwer.io/wk-logos/1.0.x... https://cdn.wolterskluwer.io/wk-logos/1.0.x/wk-brand-white.svg — 200 — 2.5 KiB — 70 ms — h2https://www.uptodate.com/app/assets/FiraSans-Light-CcuDwDV2.woffwww.uptodate.com/app/assets/FiraSan... https://www.uptodate.com/app/assets/FiraSans-Light-CcuDwDV2.woff — 200 — 180.6 KiB — 69 ms — http/1.1https://www.google.com/recaptcha/enterprise/anchor?ar=1&k=6LdCgj4qAAAAAANuTC5bIYY4si2SKXFhZbTLzYHE&co=aHR0cHM6Ly93d3cudXB0b2RhdGUuY29tOjQ0Mw..&hl=en&v=gTpTIWhbKpxADzTzkcabhXN4&size=normal&sa=validate&anchor-ms=20000&execute-ms=30000&cb=7xol0xicx3erwww.google.com/recaptcha/enterprise... https://www.google.com/recaptcha/enterprise/anchor?ar=1&k=6LdCgj4qAAAAAANuTC5bIYY4si2SKXFhZbTLzYHE&co=aHR0cHM6Ly93d3cudXB0b2RhdGUuY29tOjQ0Mw..&hl=en&v=gTpTIWhbKpxADzTzkcabhXN4&size=normal&sa=validate&anchor-ms=20000&execute-ms=30000&cb=7xol0xicx3er — 200 — 27.7 KiB — 76 ms — h3https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/styles__ltr.csswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/styles__ltr.css — 200 — 41.7 KiB — 131 ms — h2https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.jswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js — 200 — 362.4 KiB — 164 ms — h2https://www.google.com/recaptcha/enterprise/webworker.js?hl=en&v=gTpTIWhbKpxADzTzkcabhXN4www.google.com/recaptcha/enterprise... https://www.google.com/recaptcha/enterprise/webworker.js?hl=en&v=gTpTIWhbKpxADzTzkcabhXN4 — 200 — 23 B — 191 ms — h3https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.jswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js — 200 — 0 B — 20 ms — h2https://www.google.com/recaptcha/enterprise/bframe?hl=en&v=gTpTIWhbKpxADzTzkcabhXN4&k=6LdCgj4qAAAAAANuTC5bIYY4si2SKXFhZbTLzYHE&bft=0dAFcWeA5n_SVrK_DVPDLw3anHMVhjZTdBCgxVZeUdt5Sru25gBLX6nJfCG-DRrhCpekoQPOGpX3PUy1ej3SALie9WNODbWIjb3Awww.google.com/recaptcha/enterprise... https://www.google.com/recaptcha/enterprise/bframe?hl=en&v=gTpTIWhbKpxADzTzkcabhXN4&k=6LdCgj4qAAAAAANuTC5bIYY4si2SKXFhZbTLzYHE&bft=0dAFcWeA5n_SVrK_DVPDLw3anHMVhjZTdBCgxVZeUdt5Sru25gBLX6nJfCG-DRrhCpekoQPOGpX3PUy1ej3SALie9WNODbWIjb3A — 200 — 2.2 KiB — 30 ms — h3https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/styles__ltr.csswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/styles__ltr.css — 200 — 0 B — 0 ms — h2https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.jswww.gstatic.com/recaptcha/releases/... https://www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js — 200 — 0 B — 0 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100% of JavaScript execution is third-party
First-party Third-party 565ms · 20KB · $7/mo
www.uptodate.com
Other
Optional
Execution 174ms
Transfer 16 KB
Monthly Cost $2/mo
Unattributable
Other
Optional
Execution 155ms
Transfer 0 KB
Monthly Cost $2/mo
www.gstatic.com
Other
Optional
Execution 151ms
Transfer 0 KB
Unused 49%
Monthly Cost $2/mo
www.uptodate.com
Other
Optional
Execution 86ms
Transfer 4 KB
Monthly Cost $1/mo

100% 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

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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