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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
83
GRADE
B
FIX
2
REVIEW
3
PASS
7
INFO
2

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

Mobile Desktop
81
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.
81
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
91
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.

1.30 s

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

2.45 s

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

42 ms

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

0.001

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

1.83 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.

2.70 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
14
7 PASS 3 REVIEW 2 FIX
D
Page Weight Budget
Action
2.3 MB transferred, 41 requests
FIX
2.3 MB transferred, 41 requests
Info::
Page weighs 4.9 MB (2.3 MB transferred)
Info::
Fonts are 1.0 MB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 1.0 MB
Warning::
JavaScript is 668 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 668 KB
Info::
41 HTTP requests
Info::
Estimated 0.48 g CO2 per page load
2.3 MB / 2.4 MB budget
2.3 MB transferred
41 requests
0.48 g CO2 per page load
Fonts 1.0 MiB 46%
JavaScript 667.8 KiB 29%
Images 463.8 KiB 20%
CSS 69.2 KiB 3%
HTML 27.5 KiB 1%
Other 21.1 KiB 1%
Other 16.5 KiB 1%
Other 1.8 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Approaching limit

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

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

D
JS Bundles
Action
5 scripts, 421 KB unused
FIX
5 scripts, 421 KB unused
Warning::
https://learn.microsoft.com/static/assets/0.4.0337...: 363 KB unused (69%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-co...: 29 KB unused (57%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://js.monitor.azure.com/scripts/c/ms.jsll-4.m...: 29 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 421 KB
421 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://learn.microsoft.com/static/assets/0.4.03377.7675-f5f342ae/scripts/en-us/index-docs.js530 KB363 KB (69%)✓1st
https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.js52 KB29 KB (57%)✓3rd
https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.js74 KB29 KB (40%)✓3rd
https://learn.microsoft.com/_themes/docs.theme/master/en-us/_themes/global/deprecation.js2 KB—✓1st
https://learn.microsoft.com/akam/13/7e45086d10 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

B
Image Optimization
13 images, 0 KB saveable
REVIEW
13 images, 0 KB saveable
Info::
All images are well-optimized
13 images 464 KB
0 oversized -0 KB
10 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
max-age=0
REVIEW
max-age=0
Info::
Cache-Control header is set
Got: max-age=0
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

max-age=0

DirectiveValueMeaning
max-age0Cache for 0 seconds
A+
Third-Party Impact
6% third-party, 0 ms blocking
PASS
6% third-party, 0 ms blocking
Info::
Third-party code accounts for 6% of page weight (128.9 KiB of 2.3 MiB)
Info::
Third-party blocking time is low (0 ms)
94%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
JS Execution Cost
489ms total JS execution
PASS
489ms total JS execution
Info::
https://learn.microsoft.com/static/assets/0.4.0337...: 176ms CPU time
Info::
https://learn.microsoft.com/akam/13/7e45086d: 144ms CPU time
Info::
Unattributable: 106ms CPU time
Info::
https://learn.microsoft.com/en-us/: 63ms CPU time
Info::
Third-party scripts: 106ms (22% of total)

Main Thread Breakdown

Script Evaluation 39% Other 22% Style & Layout 20% Script Parsing & Compilation 14%
ScriptTotalScriptingParse/CompileParty
https://learn.microsoft.com/static/assets/0.4.03377.7675-f5f342ae/scripts/en-us/index-docs.js176ms86ms64ms1st
https://learn.microsoft.com/akam/13/7e45086d144ms91ms1ms1st
Unattributable106ms8ms0ms3rd
https://learn.microsoft.com/en-us/63ms1ms1ms1st
A+
Font Loading
2 fonts (1073 KB)
PASS
2 fonts (1073 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

1073 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 1.3 s LCP 2.4 shttps://learn.microsoft.com/static/assets/0.4.03377.7675-f5f342ae/styles/docons.f5f342a.5d7bca0a.woff2docons.f5f342a.5d7bca0a... https://learn.microsoft.com/static/assets/0.4.03377.7675-f5f342ae/styles/docons.f5f342a.5d7bca0a.woff2 — 23.0 KiB — 0 ms — font-display: swaphttps://learn.microsoft.com/static/third-party/SegoeUIVariable/SegoeUI-VF.ttfSegoeUI-VF.ttf https://learn.microsoft.com/static/third-party/SegoeUIVariable/SegoeUI-VF.ttf — 1.0 MiB — 0 ms — font-display: swap
docons.f5f342a.5d7bca0a... woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
SegoeUI-VF.ttf ttf swap
Size 1050 KB
Load time 0 ms
Start 0 ms
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 ~840 KB and ~1680 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
41 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
22% of JavaScript execution is third-party
First-party Third-party 106ms · 0KB · $1/mo
Unattributable
Other
Optional
Execution 106ms
Transfer 0 KB
Monthly Cost $1/mo

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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