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Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
89
GRADE
B
FIX
2
REVIEW
8
PASS
13
INFO
3

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

Mobile Desktop
72
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.
100
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.

2.90 s

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

2.90 s

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

45 ms

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

0.393

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

2.90 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.

5.98 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
26
13 PASS 8 REVIEW 2 FIX
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 (800.3 KiB of 800.5 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
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.

B
Image Optimization
4 images, 0 KB saveable
REVIEW
4 images, 0 KB saveable
Warning::
https://www.typescriptlang.org/images/index/stack-... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.typescriptlang.org/images/index/state-... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
4 images 16 KB
0 oversized -0 KB
2 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
834ms total JS execution
REVIEW
834ms total JS execution
Warning::
https://www.typescriptlang.org/: 382ms CPU time
Info::
https://www.typescriptlang.org/app-9b3a6007d51cd72...: 238ms CPU time
Info::
Unattributable: 146ms CPU time
Info::
https://www.typescriptlang.org/07c2af5afdf750a1639...: 68ms CPU time
Warning::
Third-party scripts: 688ms (83% of total)

Main Thread Breakdown

Script Evaluation 34% Style & Layout 25% Other 20% Script Parsing & Compilation 11% Rendering 6% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://www.typescriptlang.org/382ms11ms3ms3rd
https://www.typescriptlang.org/app-9b3a6007d51cd726e84d.js238ms206ms17ms3rd
Unattributable146ms5ms0ms1st
https://www.typescriptlang.org/07c2af5afdf750a1639f84255225a64498e50277-0400cf63dd5d2e08696b.js68ms40ms15ms3rd
B
JS Bundles
7 scripts, 98 KB unused
REVIEW
7 scripts, 98 KB unused
Warning::
https://www.typescriptlang.org/commons-a43cb90ce2f...: 42 KB unused (71%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.typescriptlang.org/app-9b3a6007d51cd72...: 30 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.typescriptlang.org/js/docsearch.js: 26 KB unused (56%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 98 KB
98 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.typescriptlang.org/commons-a43cb90ce2f9a5d36341.js62 KB42 KB (71%)✓3rd
https://www.typescriptlang.org/app-9b3a6007d51cd726e84d.js73 KB30 KB (41%)✓3rd
https://www.typescriptlang.org/js/docsearch.js46 KB26 KB (56%)✓3rd
https://www.typescriptlang.org/webpack-runtime-fdfe43fe0945c45d4db4.js3 KB—✓3rd
https://www.typescriptlang.org/07c2af5afdf750a1639f84255225a64498e50277-0400cf63dd5d2e08696b.js23 KB—✓3rd
https://www.typescriptlang.org/component---src-templates-pages-index-tsx-a723abe51a93c1625181.js40 KB—✓3rd
https://consentdeliveryfd.azurefd.net/mscc/lib/v2/wcp-consent.js277 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

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
No Cache-Control header on main HTML response
REVIEW
No Cache-Control header on main HTML response
Info::
Main HTML response has no Cache-Control header
Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.
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.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Page Weight Budget
800 KB transferred, 24 requests
PASS
800 KB transferred, 24 requests
Info::
Page weighs 1.6 MB (800 KB transferred)
Warning::
JavaScript is 525 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 525 KB
Info::
24 HTTP requests
Info::
Estimated 0.16 g CO2 per page load
800 KB / 2.4 MB budget
800 KB transferred
24 requests
0.16 g CO2 per page load
JavaScript 525.3 KiB 66%
Fonts 175.9 KiB 22%
HTML 69.2 KiB 9%
Images 16.4 KiB 2%
Other 6.2 KiB 1%
CSS 6.1 KiB 1%
Other 738 B 0%
Other 609 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

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
5 fonts (176 KB)
PASS
5 fonts (176 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

176 KB total

Render-blocking

0

of 5

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 FCP 2.9 s LCP 2.9 shttps://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-semibold.woff2segoeui-semibold.woff2 https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-semibold.woff2 — 31.1 KiB — 51 ms — font-display: swaphttps://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-regular.woff2segoeui-regular.woff2 https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-regular.woff2 — 35.5 KiB — 58 ms — font-display: swaphttps://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-light.woff2segoeui-light.woff2 https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-light.woff2 — 28.1 KiB — 58 ms — font-display: swaphttps://www.typescriptlang.org/fonts/CascadiaMono-SemiLight.woff2CascadiaMono-SemiLight.... https://www.typescriptlang.org/fonts/CascadiaMono-SemiLight.woff2 — 49.0 KiB — 127 ms — font-display: swaphttps://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-bold.woff2segoeui-bold.woff2 https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-bold.woff2 — 32.2 KiB — 57 ms — font-display: swap
segoeui-semibold.woff2 woff2 swap
Size 31 KB
Load time 51 ms
Start 907 ms
Risk FOUT — text flashes from fallback to web font
segoeui-regular.woff2 woff2 swap
Size 36 KB
Load time 58 ms
Start 907 ms
Risk FOUT — text flashes from fallback to web font
segoeui-light.woff2 woff2 swap
Size 28 KB
Load time 58 ms
Start 907 ms
Risk FOUT — text flashes from fallback to web font
CascadiaMono-SemiLight.... woff2 swap
Size 49 KB
Load time 127 ms
Start 908 ms
Risk FOUT — text flashes from fallback to web font
segoeui-bold.woff2 woff2 swap
Size 32 KB
Load time 57 ms
Start 908 ms
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)
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
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
Page uses 2 resource hint(s)

Current Resource Hints

preconnect
1
preload
1
dns-prefetch
—
prefetch
—

2 resource hints configured

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+
Server Response Intelligence
1 server-response signal(s) detected
PASS
1 server-response signal(s) detected
Info::
No `ETag` or `Last-Modified` -- conditional GET not supported
Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.
A
Page Weight Inventory
24 resources · 800 KB · 98 KB savings available
PASS
24 resources · 800 KB · 98 KB savings available
Info::
Within 1MB page-weight target
Got: 800 KB
Info::
~98 KB of savings available
Warning::
23 third-party resources (100% of weight)
Info::
1 resources over 200KB
24 resources · 800.5 KiB · 23 third-party Within 1MB page-weight target
JavaScript 66% · 525.3 KiB
Font 22% · 175.9 KiB
Document 9% · 69.2 KiB
Image 3% · 22.4 KiB
CSS 1% · 6.1 KiB
Other 0% · 1.4 KiB

~97.6 KiB of savings available

Remove unused JavaScript: 97.6 KiB
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+
JavaScript Blocking
No render-blocking JS or document.write usage detected
PASS
No render-blocking JS or document.write usage detected
Info::
No JavaScript blocking issues detected
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
No CSS performance depth issues detected
Network Waterfall
24 requests over 1618ms
INFO
0 ms 1.0 s 2.0 s 3.0 s FCP 2.9 s LCP 2.9 shttps://typescriptlang.org// https://typescriptlang.org/ — 301 — 135 B — 827 ms — h2https://www.typescriptlang.org/www.typescriptlang.org/ https://www.typescriptlang.org/ — 200 — 69.2 KiB — 14 ms — h2https://www.typescriptlang.org/css/docsearch.csswww.typescriptlang.org/css/docsearc... https://www.typescriptlang.org/css/docsearch.css — 200 — 6.1 KiB — 132 ms — h2https://www.typescriptlang.org/images/index/stack-overflow.svgwww.typescriptlang.org/images/index... https://www.typescriptlang.org/images/index/stack-overflow.svg — 200 — 13.0 KiB — 126 ms — h2https://www.typescriptlang.org/images/index/state-of-js.svgwww.typescriptlang.org/images/index... https://www.typescriptlang.org/images/index/state-of-js.svg — 200 — 3.4 KiB — 134 ms — h2https://www.typescriptlang.org/webpack-runtime-fdfe43fe0945c45d4db4.jswww.typescriptlang.org/webpack-runt... https://www.typescriptlang.org/webpack-runtime-fdfe43fe0945c45d4db4.js — 200 — 3.1 KiB — 117 ms — h2https://www.typescriptlang.org/app-9b3a6007d51cd726e84d.jswww.typescriptlang.org/app-9b3a6007... https://www.typescriptlang.org/app-9b3a6007d51cd726e84d.js — 200 — 73.0 KiB — 135 ms — h2data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAALgAAAAmCAYAAAB3X1H0AAAACXBIWXMAABYlAAAWJQFJUiTwAAAAA…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAALgAAAAmCAYAAAB3X1H0AAAACXBIWXMAABYlAAAWJQFJUiTwAAAAA… — 200 — 0 B — 0 ms — datadata:image/svg+xml,%3Csvg%20xmlns%3D'http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg'%20viewBox%3D'0%200%206%2…data:image/svg+xml,%3Csvg%20xmlns%3... data:image/svg+xml,%3Csvg%20xmlns%3D'http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg'%20viewBox%3D'0%200%206%2… — 200 — 0 B — 0 ms — datahttps://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-semibold.woff2res-1.cdn.office.net/files/fabric-c... https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-semibold.woff2 — 200 — 31.1 KiB — 51 ms — h3https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-regular.woff2res-1.cdn.office.net/files/fabric-c... https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-regular.woff2 — 200 — 35.5 KiB — 58 ms — h3https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-light.woff2res-1.cdn.office.net/files/fabric-c... https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-light.woff2 — 200 — 28.1 KiB — 58 ms — h3https://www.typescriptlang.org/fonts/CascadiaMono-SemiLight.woff2www.typescriptlang.org/fonts/Cascad... https://www.typescriptlang.org/fonts/CascadiaMono-SemiLight.woff2 — 200 — 49.0 KiB — 127 ms — h2https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-bold.woff2res-1.cdn.office.net/files/fabric-c... https://res-1.cdn.office.net/files/fabric-cdn-prod_20230815.002/assets/fonts/segoeui-westeuropean/segoeui-bold.woff2 — 200 — 32.2 KiB — 57 ms — h3https://www.typescriptlang.org/manifest.webmanifestwww.typescriptlang.org/manifest.web... https://www.typescriptlang.org/manifest.webmanifest — 200 — 738 B — 6 ms — h2https://www.typescriptlang.org/page-data/app-data.jsonwww.typescriptlang.org/page-data/ap... https://www.typescriptlang.org/page-data/app-data.json — 200 — 251 B — 120 ms — h2https://www.typescriptlang.org/page-data/index/page-data.jsonwww.typescriptlang.org/page-data/in... https://www.typescriptlang.org/page-data/index/page-data.json — 200 — 358 B — 121 ms — h2https://www.typescriptlang.org/favicon-32x32.png?v=8944a05a8b601855de116c8a56d3b3aewww.typescriptlang.org/favicon-32x3... https://www.typescriptlang.org/favicon-32x32.png?v=8944a05a8b601855de116c8a56d3b3ae — 200 — 1.4 KiB — 124 ms — h2https://www.typescriptlang.org/icons/icon-144x144.png?v=8944a05a8b601855de116c8a56d3b3aewww.typescriptlang.org/icons/icon-1... https://www.typescriptlang.org/icons/icon-144x144.png?v=8944a05a8b601855de116c8a56d3b3ae — 200 — 4.7 KiB — 201 ms — h2https://www.typescriptlang.org/commons-a43cb90ce2f9a5d36341.jswww.typescriptlang.org/commons-a43c... https://www.typescriptlang.org/commons-a43cb90ce2f9a5d36341.js — 200 — 62.5 KiB — 131 ms — h2https://www.typescriptlang.org/07c2af5afdf750a1639f84255225a64498e50277-0400cf63dd5d2e08696b.jswww.typescriptlang.org/07c2af5afdf7... https://www.typescriptlang.org/07c2af5afdf750a1639f84255225a64498e50277-0400cf63dd5d2e08696b.js — 200 — 23.2 KiB — 128 ms — h2https://www.typescriptlang.org/component---src-templates-pages-index-tsx-a723abe51a93c1625181.jswww.typescriptlang.org/component---... https://www.typescriptlang.org/component---src-templates-pages-index-tsx-a723abe51a93c1625181.js — 200 — 39.9 KiB — 136 ms — h2https://consentdeliveryfd.azurefd.net/mscc/lib/v2/wcp-consent.jsconsentdeliveryfd.azurefd.net/mscc/... https://consentdeliveryfd.azurefd.net/mscc/lib/v2/wcp-consent.js — 200 — 277.4 KiB — 296 ms — h2https://www.typescriptlang.org/js/docsearch.jswww.typescriptlang.org/js/docsearch... https://www.typescriptlang.org/js/docsearch.js — 200 — 46.2 KiB — 125 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
83% of JavaScript execution is third-party
First-party Third-party 688ms · 165KB · $2/mo
www.typescriptlang.org
Other
Costly
Execution 382ms
Transfer 69 KB
Monthly Cost $1/mo
www.typescriptlang.org
Other
Costly
Execution 238ms
Transfer 73 KB
Unused 41%
Monthly Cost $1/mo
www.typescriptlang.org
Other
Optional
Execution 68ms
Transfer 23 KB
Monthly Cost $0/mo

These scripts may cost more than they're worth

  • www.typescriptlang.org adds 382ms and costs ~$1/month
  • www.typescriptlang.org adds 238ms and costs ~$1/month

83% 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

www.typescriptlang.org takes 382ms 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

www.typescriptlang.org takes 238ms 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

Image Optimization
3 images, 16 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

3

Total Size

16 KB

2 missing dimensions 3 missing lazy loading
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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