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Performance

· 21 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
80
GRADE
B
FIX
3
REVIEW
6
PASS
9
INFO
3

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

Mobile Desktop
98
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
90
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.
80
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.

847 ms

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

925 ms

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

14 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.

930 ms

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

2.37 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
21
9 PASS 6 REVIEW 3 FIX
D
Third-Party Impact
Action
62% third-party, 0 ms blocking
FIX
62% third-party, 0 ms blocking
Warning::
Third-party code accounts for 62% of page weight (908.0 KiB of 1.4 MiB)
Info::
Third-party blocking time is low (0 ms)
38%
62%
First-party Third-party
F
JS Bundles
Action
46 scripts, 622 KB unused
FIX
46 scripts, 622 KB unused
Warning::
https://securepubads.g.doubleclick.net/pagead/mana...: 140 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://edge.aditude.io/prebid/9.30.0.js?fork=1&v=...: 100 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://stackoverflow.com/Content/Js/full-anon.en....: 95 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://accounts.google.com/gsi/client: 72 KB unused (75%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://raven-static.aditude.io/prod/1.20.0-69wxiu...: 63 KB unused (60%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 622 KB
622 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604300101/pubads_impl.js189 KB140 KB (74%)✓3rd
https://edge.aditude.io/prebid/9.30.0.js?fork=1&v=6167788a58e716d678c6d136265c856c&modules=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 KB100 KB (74%)✓3rd
https://stackoverflow.com/Content/Js/full-anon.en.js?v=1184f324f5d2129 KB95 KB (74%)✓1st
https://accounts.google.com/gsi/client96 KB72 KB (75%)✓3rd
https://raven-static.aditude.io/prod/1.20.0-69wxiu/raven.js106 KB63 KB (60%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-WCZ03SZFCQ155 KB62 KB (40%)✓3rd
https://dn0qt3r0xannq.cloudfront.net/stackoverflow-M6HzSe6yue/mapping.base/prebid-wrapper.js81 KB37 KB (45%)✓3rd
https://stackoverflow.com/Content/Js/webpack-chunks/svelte.en.js?v=f773033c4e0b32 KB32 KB (99%)✓1st
https://stackoverflow.com/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js/stacks.min.js?v=c7bcc7a1b4fd30 KB21 KB (69%)✓1st
https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte.en.js?v=297d3b9a88f613 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
63 resources · 1.4 MB · 622 KB savings available
FIX
63 resources · 1.4 MB · 622 KB savings available
Warning::
Page weight 1.4 MB exceeds 1 MB target by 434 KB
Got: 1.4 MB Expected: ≤ 1 MB
Info::
~622 KB of savings available
Warning::
31 third-party resources (62% of weight)
63 resources · 1.4 MiB · 31 third-party 434.4 KiB over 1MB target
JavaScript 81% · 1.2 MiB
CSS 14% · 207.3 KiB
Document 2% · 35.2 KiB
Other 2% · 27.8 KiB
Image 0% · 1.6 KiB

~621.8 KiB of savings available

Remove unused JavaScript: 621.8 KiB
B
Page Weight Budget
1.4 MB transferred, 63 requests
REVIEW
1.4 MB transferred, 63 requests
Info::
Page weighs 5.2 MB (1.4 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::
CSS is 207 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 207 KB
Info::
63 HTTP requests
Info::
Estimated 0.30 g CO2 per page load
1.4 MB / 2.4 MB budget
1.4 MB transferred
63 requests
0.30 g CO2 per page load
JavaScript 1.2 MiB 81%
CSS 207.3 KiB 14%
HTML 35.2 KiB 2%
Other 24.2 KiB 2%
Other 3.3 KiB 0%
Other 1006 B 0%
Images 953 B 0%
0 2.4 MB 4.9 MB
Under 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

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

B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
C
Compression Algorithm
Action
Main response served uncompressed
REVIEW
Main response served uncompressed
Info::
Main HTML response has no Content-Encoding (uncompressed)
The main HTML document is served without compression. The Text Compression section above lists the broader picture; for the main response specifically, even gzip would shave ~70-80% off most text payloads.
B
Main HTML Cache-Control
Cache-Control present but without max-age
REVIEW
Cache-Control present but without max-age
Info::
Main HTML Cache-Control has no max-age: private
Got: private
B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
B
HTTP Caching
private
REVIEW
private
Info::
Cache-Control header is set
Got: private
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
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
Image Optimization
2 images, 0 KB saveable
PASS
2 images, 0 KB saveable
Info::
All images are well-optimized
2 images 1 KB
0 oversized -0 KB
2 legacy format
0 missing dimensions CLS risk
A+
JS Execution Cost
309ms total JS execution
PASS
309ms total JS execution
Info::
https://stackoverflow.com/users/login: 71ms CPU time
Info::
https://stackoverflow.com/Content/Js/islands/homep...: 64ms CPU time
Info::
https://securepubads.g.doubleclick.net/pagead/mana...: 64ms CPU time
Info::
Unattributable: 57ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-WCZ0...: 52ms CPU time
Warning::
Third-party scripts: 174ms (56% of total)

Main Thread Breakdown

Script Evaluation 66% Script Parsing & Compilation 11% Other 10% Style & Layout 8% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://stackoverflow.com/users/login71ms13ms3ms1st
https://stackoverflow.com/Content/Js/islands/homepage-wizard.en.js?v=a74b3480697c64ms48ms1ms1st
https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604300101/pubads_impl.js64ms53ms10ms3rd
Unattributable57ms3ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-WCZ03SZFCQ52ms44ms7ms3rd
A+
Font Loading
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
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+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
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 2440ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 847 ms LCP 925 mshttps://stackoverflow.com/users/login/users/login https://stackoverflow.com/users/login — 200 — 35.2 KiB — 229 ms — h2https://cdn.cookielaw.org/scripttemplates/gpp.stub.jscdn.cookielaw.org/scripttemplates/g... https://cdn.cookielaw.org/scripttemplates/gpp.stub.js — -1 — 0 B — 70 ms — https://cdn.cookielaw.org/scripttemplates/otSDKStub.jscdn.cookielaw.org/scripttemplates/o... https://cdn.cookielaw.org/scripttemplates/otSDKStub.js — -1 — 0 B — 61 ms — https://stackoverflow.com/Content/Js/google-analytics.en.js?v=48615a9a9bc4/Content/Js/google-analytics.en.js?... https://stackoverflow.com/Content/Js/google-analytics.en.js?v=48615a9a9bc4 — 200 — 2.4 KiB — 31 ms — h2https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.jsajax.googleapis.com/ajax/libs/jquer... https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js — 200 — 30.4 KiB — 124 ms — h2https://stackoverflow.com/Content/Js/stub.en.js?v=b6c076cce061/Content/Js/stub.en.js?v=b6c076cce0... https://stackoverflow.com/Content/Js/stub.en.js?v=b6c076cce061 — 200 — 18.1 KiB — 33 ms — h2https://stackoverflow.com/Content/Shared/stacks.css?v=b2264ccf0463/Content/Shared/stacks.css?v=b2264c... https://stackoverflow.com/Content/Shared/stacks.css?v=b2264ccf0463 — 200 — 110.2 KiB — 60 ms — h2https://stackoverflow.com/Content/Sites/stackoverflow/primary.css?v=880dfade9e7f/Content/Sites/stackoverflow/primar... https://stackoverflow.com/Content/Sites/stackoverflow/primary.css?v=880dfade9e7f — 200 — 74.3 KiB — 59 ms — h2https://stackoverflow.com/Content/Sites/stackoverflow/secondary.css?v=2a409df786e1/Content/Sites/stackoverflow/second... https://stackoverflow.com/Content/Sites/stackoverflow/secondary.css?v=2a409df786e1 — 200 — 17.5 KiB — 60 ms — h2https://stackoverflow.com/Content/Js/auth.en.js?v=4ab5d8f5659f/Content/Js/auth.en.js?v=4ab5d8f565... https://stackoverflow.com/Content/Js/auth.en.js?v=4ab5d8f5659f — 200 — 3.5 KiB — 30 ms — h2https://stackoverflow.com/Content/Shared/Channels/channels.css?v=d431b1be5a03/Content/Shared/Channels/channels.c... https://stackoverflow.com/Content/Shared/Channels/channels.css?v=d431b1be5a03 — 200 — 4.7 KiB — 27 ms — h2https://stackoverflow.com/px.js?ch=1/px.js?ch=1 https://stackoverflow.com/px.js?ch=1 — 200 — 370 B — 158 ms — h2https://stackoverflow.com/px.js?ch=2/px.js?ch=2 https://stackoverflow.com/px.js?ch=2 — 200 — 548 B — 151 ms — h2https://stackoverflow.com/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js/stacks.min.js?v=c7bcc7a1b4fd/Content/Js/third-party/npm/@stacko... https://stackoverflow.com/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js/stacks.min.js?v=c7bcc7a1b4fd — 200 — 30.5 KiB — 27 ms — h2https://stackoverflow.com/Content/Js/sprinkles/cookie-consent.en.js?v=7ee6963139c5/Content/Js/sprinkles/cookie-consen... https://stackoverflow.com/Content/Js/sprinkles/cookie-consent.en.js?v=7ee6963139c5 — 200 — 913 B — 26 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/svelte.en.js?v=f773033c4e0b/Content/Js/webpack-chunks/svelte.e... https://stackoverflow.com/Content/Js/webpack-chunks/svelte.en.js?v=f773033c4e0b — 200 — 32.1 KiB — 35 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte.en.js?v=297d3b9a88f6/Content/Js/webpack-chunks/stacks-s... https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte.en.js?v=297d3b9a88f6 — 200 — 12.8 KiB — 36 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/9366.en.js?v=c8d4e4e64bf3/Content/Js/webpack-chunks/9366.en.... https://stackoverflow.com/Content/Js/webpack-chunks/9366.en.js?v=c8d4e4e64bf3 — 200 — 8.5 KiB — 32 ms — h2https://stackoverflow.com/Content/Js/islands/signup-modal.en.js?v=f64ec881ea96/Content/Js/islands/signup-modal.en... https://stackoverflow.com/Content/Js/islands/signup-modal.en.js?v=f64ec881ea96 — 200 — 8.4 KiB — 36 ms — h2https://stackoverflow.com/Content/Js/islands/one-tap.en.js?v=102f0378a2cf/Content/Js/islands/one-tap.en.js?v... https://stackoverflow.com/Content/Js/islands/one-tap.en.js?v=102f0378a2cf — 200 — 1.7 KiB — 37 ms — h2https://stackoverflow.com/Content/Js/sprinkles/left-nav-events.en.js?v=2ac13fd60bf6/Content/Js/sprinkles/left-nav-even... https://stackoverflow.com/Content/Js/sprinkles/left-nav-events.en.js?v=2ac13fd60bf6 — 200 — 1.1 KiB — 33 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte-labs.en.js?v=b9cf031e2bdd/Content/Js/webpack-chunks/stacks-s... https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte-labs.en.js?v=b9cf031e2bdd — 200 — 7.8 KiB — 31 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/8339.en.js?v=4cb8dd34a7f9/Content/Js/webpack-chunks/8339.en.... https://stackoverflow.com/Content/Js/webpack-chunks/8339.en.js?v=4cb8dd34a7f9 — 200 — 5.0 KiB — 29 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/7663.en.js?v=c67f16729ba4/Content/Js/webpack-chunks/7663.en.... https://stackoverflow.com/Content/Js/webpack-chunks/7663.en.js?v=c67f16729ba4 — 200 — 7.4 KiB — 37 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/3696.en.js?v=7ef09fb6562b/Content/Js/webpack-chunks/3696.en.... https://stackoverflow.com/Content/Js/webpack-chunks/3696.en.js?v=7ef09fb6562b — 200 — 2.1 KiB — 40 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/2458.en.js?v=33cc3da05f78/Content/Js/webpack-chunks/2458.en.... https://stackoverflow.com/Content/Js/webpack-chunks/2458.en.js?v=33cc3da05f78 — 200 — 795 B — 46 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/620.en.js?v=a432091814d8/Content/Js/webpack-chunks/620.en.j... https://stackoverflow.com/Content/Js/webpack-chunks/620.en.js?v=a432091814d8 — 200 — 1.7 KiB — 28 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/9001.en.js?v=3a153d433746/Content/Js/webpack-chunks/9001.en.... https://stackoverflow.com/Content/Js/webpack-chunks/9001.en.js?v=3a153d433746 — 200 — 5.2 KiB — 40 ms — h2https://stackoverflow.com/Content/Js/islands/homepage-wizard.en.js?v=a74b3480697c/Content/Js/islands/homepage-wizard... https://stackoverflow.com/Content/Js/islands/homepage-wizard.en.js?v=a74b3480697c — 200 — 16.1 KiB — 45 ms — h2https://www.googletagmanager.com/gtag/js?id=G-WCZ03SZFCQwww.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-WCZ03SZFCQ — 200 — 154.6 KiB — 188 ms — h2
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 847 ms LCP 925 mshttps://stackoverflow.com/users/login/users/login https://stackoverflow.com/users/login — 200 — 35.2 KiB — 229 ms — h2https://cdn.cookielaw.org/scripttemplates/gpp.stub.jscdn.cookielaw.org/scripttemplates/g... https://cdn.cookielaw.org/scripttemplates/gpp.stub.js — -1 — 0 B — 70 ms — https://cdn.cookielaw.org/scripttemplates/otSDKStub.jscdn.cookielaw.org/scripttemplates/o... https://cdn.cookielaw.org/scripttemplates/otSDKStub.js — -1 — 0 B — 61 ms — https://stackoverflow.com/Content/Js/google-analytics.en.js?v=48615a9a9bc4/Content/Js/google-analytics.en.js?... https://stackoverflow.com/Content/Js/google-analytics.en.js?v=48615a9a9bc4 — 200 — 2.4 KiB — 31 ms — h2https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.jsajax.googleapis.com/ajax/libs/jquer... https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js — 200 — 30.4 KiB — 124 ms — h2https://stackoverflow.com/Content/Js/stub.en.js?v=b6c076cce061/Content/Js/stub.en.js?v=b6c076cce0... https://stackoverflow.com/Content/Js/stub.en.js?v=b6c076cce061 — 200 — 18.1 KiB — 33 ms — h2https://stackoverflow.com/Content/Shared/stacks.css?v=b2264ccf0463/Content/Shared/stacks.css?v=b2264c... https://stackoverflow.com/Content/Shared/stacks.css?v=b2264ccf0463 — 200 — 110.2 KiB — 60 ms — h2https://stackoverflow.com/Content/Sites/stackoverflow/primary.css?v=880dfade9e7f/Content/Sites/stackoverflow/primar... https://stackoverflow.com/Content/Sites/stackoverflow/primary.css?v=880dfade9e7f — 200 — 74.3 KiB — 59 ms — h2https://stackoverflow.com/Content/Sites/stackoverflow/secondary.css?v=2a409df786e1/Content/Sites/stackoverflow/second... https://stackoverflow.com/Content/Sites/stackoverflow/secondary.css?v=2a409df786e1 — 200 — 17.5 KiB — 60 ms — h2https://stackoverflow.com/Content/Js/auth.en.js?v=4ab5d8f5659f/Content/Js/auth.en.js?v=4ab5d8f565... https://stackoverflow.com/Content/Js/auth.en.js?v=4ab5d8f5659f — 200 — 3.5 KiB — 30 ms — h2https://stackoverflow.com/Content/Shared/Channels/channels.css?v=d431b1be5a03/Content/Shared/Channels/channels.c... https://stackoverflow.com/Content/Shared/Channels/channels.css?v=d431b1be5a03 — 200 — 4.7 KiB — 27 ms — h2https://stackoverflow.com/px.js?ch=1/px.js?ch=1 https://stackoverflow.com/px.js?ch=1 — 200 — 370 B — 158 ms — h2https://stackoverflow.com/px.js?ch=2/px.js?ch=2 https://stackoverflow.com/px.js?ch=2 — 200 — 548 B — 151 ms — h2https://stackoverflow.com/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js/stacks.min.js?v=c7bcc7a1b4fd/Content/Js/third-party/npm/@stacko... https://stackoverflow.com/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js/stacks.min.js?v=c7bcc7a1b4fd — 200 — 30.5 KiB — 27 ms — h2https://stackoverflow.com/Content/Js/sprinkles/cookie-consent.en.js?v=7ee6963139c5/Content/Js/sprinkles/cookie-consen... https://stackoverflow.com/Content/Js/sprinkles/cookie-consent.en.js?v=7ee6963139c5 — 200 — 913 B — 26 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/svelte.en.js?v=f773033c4e0b/Content/Js/webpack-chunks/svelte.e... https://stackoverflow.com/Content/Js/webpack-chunks/svelte.en.js?v=f773033c4e0b — 200 — 32.1 KiB — 35 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte.en.js?v=297d3b9a88f6/Content/Js/webpack-chunks/stacks-s... https://stackoverflow.com/Content/Js/webpack-chunks/stacks-svelte.en.js?v=297d3b9a88f6 — 200 — 12.8 KiB — 36 ms — h2https://stackoverflow.com/Content/Js/webpack-chunks/9366.en.js?v=c8d4e4e64bf3/Content/Js/webpack-chunks/9366.en.... https://stackoverflow.com/Content/Js/webpack-chunks/9366.en.js?v=c8d4e4e64bf3 — 200 — 8.5 KiB — 32 ms — h2https://stackoverflow.com/Content/Js/islands/signup-modal.en.js?v=f64ec881ea96/Content/Js/islands/signup-modal.en... https://stackoverflow.com/Content/Js/islands/signup-modal.en.js?v=f64ec881ea96 — 200 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h3https://geo-location.prebid.cloud/v1/geogeo-location.prebid.cloud/v1/geo https://geo-location.prebid.cloud/v1/geo — 200 — 460 B — 58 ms — h2https://securepubads.g.doubleclick.net/pagead/managed/dict/m202605070101/gptsecurepubads.g.doubleclick.net/page... https://securepubads.g.doubleclick.net/pagead/managed/dict/m202605070101/gpt — 200 — 23.1 KiB — 31 ms — h3https://raven-static.aditude.io/prod/1.20.0-69wxiu/raven.jsraven-static.aditude.io/prod/1.20.0... https://raven-static.aditude.io/prod/1.20.0-69wxiu/raven.js — 200 — 106.1 KiB — 57 ms — h2https://geo.aditude.io/ravengeo.aditude.io/raven https://geo.aditude.io/raven — 200 — 310 B — 61 ms — h2https://dn0qt3r0xannq.cloudfront.net/components/htl-prebid-floors-component.761185965871a7d8a86f.jsdn0qt3r0xannq.cloudfront.net/compon... https://dn0qt3r0xannq.cloudfront.net/components/htl-prebid-floors-component.761185965871a7d8a86f.js — 200 — 2.9 KiB — 20 ms — 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200 — 642 B — 38 ms — h2https://stackoverflow.com/Content/Sites/stackoverflow/Img/favicon.svg?v=916c1b91e14c/Content/Sites/stackoverflow/Img/fa... https://stackoverflow.com/Content/Sites/stackoverflow/Img/favicon.svg?v=916c1b91e14c — 200 — 722 B — 26 ms — h2https://raven-static.aditude.io/prod/1.20.0-69wxiu/prebid-analytics.1d629f71b0308758a727.module.jsraven-static.aditude.io/prod/1.20.0... https://raven-static.aditude.io/prod/1.20.0-69wxiu/prebid-analytics.1d629f71b0308758a727.module.js — 200 — 5.6 KiB — 25 ms — h2https://raven-edge.aditude.io/api/v1/revenuesourcemaps/ebZqTKyz4DUJraven-edge.aditude.io/api/v1/revenu... https://raven-edge.aditude.io/api/v1/revenuesourcemaps/ebZqTKyz4DUJ — 200 — 1.1 KiB — 23 ms — h2https://ams-pageview-public.s3.amazonaws.com/1x1-pixel.png?id=b1ffe3826ebcams-pageview-public.s3.amazonaws.co... https://ams-pageview-public.s3.amazonaws.com/1x1-pixel.png?id=b1ffe3826ebc — 200 — 468 B — 342 ms — http/1.1
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
56% of JavaScript execution is third-party
First-party Third-party 174ms · 344KB · $2/mo
securepubads.g.doubleclick.net
Other
Optional
Execution 64ms
Transfer 189 KB
Unused 74%
Monthly Cost $1/mo
Unattributable
Other
Optional
Execution 57ms
Transfer 0 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 52ms
Transfer 155 KB
Unused 40%
Monthly Cost $1/mo

56% 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

74% of securepubads.g.doubleclick.net'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

Real-User Performance (CrUX)
Field metrics from the Chrome User Experience Report
INFO

Chrome User Experience (CrUX)

Real-user metrics from the Chrome UX Report (2026-04-10 — 2026-05-07)

LCP (p75)

1510 ms

88% good

INP (p75)

93 ms

92% good

CLS (p75)

0.000

99% good

FCP (p75)

1211 ms

TTFB (p75)

690 ms

This origin passes Core Web Vitals assessment
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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