Skip to content
https://msdn.com

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
77
GRADE
C
FIX
5
REVIEW
3
PASS
7
INFO
2

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

Mobile Desktop
56
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.

9.24 s

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

9.61 s

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

86 ms

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

0.016

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

9.24 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.

14.99 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
7 PASS 3 REVIEW 5 FIX
D
Page Weight Budget
Action
2.3 MB transferred, 37 requests
FIX
2.3 MB transferred, 37 requests
Info::
Page weighs 4.9 MB (2.3 MB transferred)
Info::
Fonts are 1.2 MB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 1.2 MB
Warning::
JavaScript is 883 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 883 KB
Info::
37 HTTP requests
Info::
Estimated 0.48 g CO2 per page load
2.3 MB / 2.4 MB budget
2.3 MB transferred
37 requests
0.48 g CO2 per page load
Fonts 1.2 MiB 51%
JavaScript 883.5 KiB 38%
Images 123.7 KiB 5%
CSS 69.2 KiB 3%
HTML 27.5 KiB 1%
Other 16.6 KiB 1%
Other 15.8 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
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 (2.3 MiB of 2.3 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
D
JS Bundles
Action
5 scripts, 390 KB unused
FIX
5 scripts, 390 KB unused
Warning::
https://learn.microsoft.com/static/assets/0.4.0339...: 361 KB unused (69%)
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: 390 KB
390 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/scripts/en-us/index-docs.js524 KB361 KB (69%)✓3rd
https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.js74 KB29 KB (40%)✓3rd
https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.js274 KB—✓3rd
https://learn.microsoft.com/_themes/docs.theme/master/en-us/_themes/global/deprecation.js2 KB—✓3rd
https://learn.microsoft.com/akam/13/66ae903f10 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

D
Page Weight Inventory
Action
37 resources · 2.3 MB · 390 KB savings available
FIX
37 resources · 2.3 MB · 390 KB savings available
Warning::
Page weight 1.3 MB over 1MB target
Got: 2.3 MB Expected: ≤ 1 MB
Info::
~390 KB of savings available
Warning::
36 third-party resources (100% of weight)
Info::
3 resources over 200KB
37 resources · 2.3 MiB · 36 third-party 1.3 MiB over 1MB target
Font 51% · 1.2 MiB
JavaScript 38% · 883.5 KiB
Image 5% · 126.1 KiB
CSS 3% · 69.2 KiB
Other 1% · 30.9 KiB
Document 1% · 28.3 KiB

~390.1 KiB of savings available

Remove unused JavaScript: 390.1 KiB
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
10 images, 0 KB saveable
REVIEW
10 images, 0 KB saveable
Info::
All images are well-optimized
10 images 124 KB
0 oversized -0 KB
7 legacy format
0 missing dimensions CLS risk
C
JS Execution Cost
Action
1748ms total JS execution
REVIEW
1748ms total JS execution
Warning::
https://learn.microsoft.com/static/assets/0.4.0339...: 627ms CPU time
Warning::
https://learn.microsoft.com/akam/13/66ae903f: 486ms CPU time
Warning::
Unattributable: 310ms CPU time
Info::
https://learn.microsoft.com/en-us/: 209ms CPU time
Info::
https://js.monitor.azure.com/scripts/c/ms.jsll-4.m...: 116ms CPU time
Warning::
Third-party scripts: 1748ms (100% of total)

Main Thread Breakdown

Script Evaluation 41% Other 20% Script Parsing & Compilation 17% Style & Layout 16%
ScriptTotalScriptingParse/CompileParty
https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/scripts/en-us/index-docs.js627ms320ms251ms3rd
https://learn.microsoft.com/akam/13/66ae903f486ms320ms4ms3rd
Unattributable310ms13ms0ms3rd
https://learn.microsoft.com/en-us/209ms6ms2ms3rd
https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.js116ms74ms21ms3rd
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
3 fonts (1191 KB)
PASS
3 fonts (1191 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

1191 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 FCP 9.2 s LCP 9.6 shttps://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/docons.e9637cb.7a2385d0.woff2docons.e9637cb.7a2385d0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/docons.e9637cb.7a2385d0.woff2 — 24.1 KiB — 31 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 — 48 ms — font-display: swaphttps://learn.microsoft.com/static/third-party/SegoeUIWeb/1.01.206/SegoeUI-Roman-VF_web.woff2SegoeUI-Roman-VF_web.woff2 https://learn.microsoft.com/static/third-party/SegoeUIWeb/1.01.206/SegoeUI-Roman-VF_web.woff2 — 116.3 KiB — 49 ms — font-display: swap
docons.e9637cb.7a2385d0... woff2 swap
Size 24 KB
Load time 31 ms
Start 2.0 s
Risk FOUT — text flashes from fallback to web font
SegoeUI-VF.ttf ttf swap
Size 1050 KB
Load time 48 ms
Start 2.0 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
SegoeUI-Roman-VF_web.woff2 woff2 swap
Size 116 KB
Load time 49 ms
Start 2.0 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
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 ~899 KB and ~1798 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
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
Network Waterfall
37 requests over 4163ms
INFO
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s FCP 9.2 s LCP 9.6 shttps://msdn.com// https://msdn.com/ — 301 — 131 B — 309 ms — h2https://msdn.microsoft.com/msdn.microsoft.com/ https://msdn.microsoft.com/ — 301 — 501 B — 806 ms — h2https://learn.microsoft.com/learn.microsoft.com/ https://learn.microsoft.com/ — 302 — 1.8 KiB — 145 ms — h2https://learn.microsoft.com/en-us/learn.microsoft.com/en-us/ https://learn.microsoft.com/en-us/ — 200 — 27.5 KiB — 34 ms — h2https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/site.csslearn.microsoft.com/static/assets/0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/site.css — 200 — 69.2 KiB — 17 ms — h2https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.jswcpstatic.microsoft.com/mscc/lib/v2... https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.js — 200 — 273.7 KiB — 430 ms — h2https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.jsjs.monitor.azure.com/scripts/c/ms.j... https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.js — 200 — 73.6 KiB — 148 ms — h2https://learn.microsoft.com/_themes/docs.theme/master/en-us/_themes/global/deprecation.jslearn.microsoft.com/_themes/docs.th... https://learn.microsoft.com/_themes/docs.theme/master/en-us/_themes/global/deprecation.js — 200 — 2.5 KiB — 151 ms — h2https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/scripts/en-us/index-docs.jslearn.microsoft.com/static/assets/0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/scripts/en-us/index-docs.js — 200 — 524.1 KiB — 41 ms — h2https://learn.microsoft.com/akam/13/66ae903flearn.microsoft.com/akam/13/66ae903... https://learn.microsoft.com/akam/13/66ae903f — 200 — 9.6 KiB — 14 ms — h2https://learn.microsoft.com/en-us/content-nav/site-header/site-header.json?learn.microsoft.com/en-us/content-n... https://learn.microsoft.com/en-us/content-nav/site-header/site-header.json? — 200 — 4.1 KiB — 24 ms — h2https://learn.microsoft.com/en-us/feature-rollout.jsonlearn.microsoft.com/en-us/feature-r... https://learn.microsoft.com/en-us/feature-rollout.json — 200 — 3.1 KiB — 25 ms — h2data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 2048 2048' %3E%3Cpath d='…www.w3.org/2000/svg' viewBox='0 0 2... data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 2048 2048' %3E%3Cpath d='… — 200 — 0 B — 0 ms — datadata:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAASwAAACWCAYAAABkW7XSAAAQAElEQVR4AeycCXzVNbbHk3tbyl5AN…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAASwAAACWCAYAAABkW7XSAAAQAElEQVR4AeycCXzVNbbHk3tbyl5AN… — 200 — 0 B — 0 ms — datadata:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACGFjVEwAAAABAAAAAcMq2TYAAAANS…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACGFjVEwAAAABAAAAAcMq2TYAAAANS… — 200 — 0 B — 0 ms — datahttps://learn.microsoft.com/en-us/banners/index.jsonlearn.microsoft.com/en-us/banners/i... https://learn.microsoft.com/en-us/banners/index.json — 200 — 9.4 KiB — 14 ms — h2https://learn.microsoft.com/en-us/media/event-banners/banner-build-2026.pnglearn.microsoft.com/en-us/media/eve... https://learn.microsoft.com/en-us/media/event-banners/banner-build-2026.png — 200 — 62.0 KiB — 14 ms — h2https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/docons.e9637cb.7a2385d0.woff2learn.microsoft.com/static/assets/0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/docons.e9637cb.7a2385d0.woff2 — 200 — 24.1 KiB — 31 ms — h2https://learn.microsoft.com/static/third-party/SegoeUIVariable/SegoeUI-VF.ttflearn.microsoft.com/static/third-pa... https://learn.microsoft.com/static/third-party/SegoeUIVariable/SegoeUI-VF.ttf — 200 — 1.0 MiB — 48 ms — h2https://learn.microsoft.com/static/third-party/SegoeUIWeb/1.01.206/SegoeUI-Roman-VF_web.woff2learn.microsoft.com/static/third-pa... https://learn.microsoft.com/static/third-party/SegoeUIWeb/1.01.206/SegoeUI-Roman-VF_web.woff2 — 200 — 116.3 KiB — 49 ms — h2https://learn.microsoft.com/media/common/ai-microchip.svglearn.microsoft.com/media/common/ai... https://learn.microsoft.com/media/common/ai-microchip.svg — 302 — 1.8 KiB — 129 ms — h2https://learn.microsoft.com/media/logos/logo_azure.svglearn.microsoft.com/media/logos/log... https://learn.microsoft.com/media/logos/logo_azure.svg — 302 — 1.8 KiB — 139 ms — h2https://learn.microsoft.com/media/logos/logo_copilot.svglearn.microsoft.com/media/logos/log... https://learn.microsoft.com/media/logos/logo_copilot.svg — 302 — 1.8 KiB — 383 ms — h2https://learn.microsoft.com/media/learn/instructor-led-badge.svglearn.microsoft.com/media/learn/ins... https://learn.microsoft.com/media/learn/instructor-led-badge.svg — 302 — 1.8 KiB — 139 ms — h2https://learn.microsoft.com/training/achievements/generic-badge.svglearn.microsoft.com/training/achiev... https://learn.microsoft.com/training/achievements/generic-badge.svg — 302 — 1.8 KiB — 139 ms — h2https://learn.microsoft.com/media/home-and-directory/icon-azure-cloud.svglearn.microsoft.com/media/home-and-... https://learn.microsoft.com/media/home-and-directory/icon-azure-cloud.svg — 302 — 1.8 KiB — 160 ms — h2https://learn.microsoft.com/favicon.icolearn.microsoft.com/favicon.ico https://learn.microsoft.com/favicon.ico — 200 — 2.4 KiB — 13 ms — h2https://learn.microsoft.com/en-us/media/common/ai-microchip.svglearn.microsoft.com/en-us/media/com... https://learn.microsoft.com/en-us/media/common/ai-microchip.svg — 200 — 7.1 KiB — 60 ms — h2https://learn.microsoft.com/en-us/media/logos/logo_azure.svglearn.microsoft.com/en-us/media/log... https://learn.microsoft.com/en-us/media/logos/logo_azure.svg — 200 — 2.8 KiB — 89 ms — h2https://learn.microsoft.com/en-us/media/learn/instructor-led-badge.svglearn.microsoft.com/en-us/media/lea... https://learn.microsoft.com/en-us/media/learn/instructor-led-badge.svg — 200 — 5.9 KiB — 55 ms — h2
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s FCP 9.2 s LCP 9.6 shttps://msdn.com// https://msdn.com/ — 301 — 131 B — 309 ms — h2https://msdn.microsoft.com/msdn.microsoft.com/ https://msdn.microsoft.com/ — 301 — 501 B — 806 ms — h2https://learn.microsoft.com/learn.microsoft.com/ https://learn.microsoft.com/ — 302 — 1.8 KiB — 145 ms — h2https://learn.microsoft.com/en-us/learn.microsoft.com/en-us/ https://learn.microsoft.com/en-us/ — 200 — 27.5 KiB — 34 ms — h2https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/site.csslearn.microsoft.com/static/assets/0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/site.css — 200 — 69.2 KiB — 17 ms — h2https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.jswcpstatic.microsoft.com/mscc/lib/v2... https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.js — 200 — 273.7 KiB — 430 ms — h2https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.jsjs.monitor.azure.com/scripts/c/ms.j... https://js.monitor.azure.com/scripts/c/ms.jsll-4.min.js — 200 — 73.6 KiB — 148 ms — h2https://learn.microsoft.com/_themes/docs.theme/master/en-us/_themes/global/deprecation.jslearn.microsoft.com/_themes/docs.th... https://learn.microsoft.com/_themes/docs.theme/master/en-us/_themes/global/deprecation.js — 200 — 2.5 KiB — 151 ms — h2https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/scripts/en-us/index-docs.jslearn.microsoft.com/static/assets/0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/scripts/en-us/index-docs.js — 200 — 524.1 KiB — 41 ms — h2https://learn.microsoft.com/akam/13/66ae903flearn.microsoft.com/akam/13/66ae903... https://learn.microsoft.com/akam/13/66ae903f — 200 — 9.6 KiB — 14 ms — h2https://learn.microsoft.com/en-us/content-nav/site-header/site-header.json?learn.microsoft.com/en-us/content-n... https://learn.microsoft.com/en-us/content-nav/site-header/site-header.json? — 200 — 4.1 KiB — 24 ms — h2https://learn.microsoft.com/en-us/feature-rollout.jsonlearn.microsoft.com/en-us/feature-r... https://learn.microsoft.com/en-us/feature-rollout.json — 200 — 3.1 KiB — 25 ms — h2data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 2048 2048' %3E%3Cpath d='…www.w3.org/2000/svg' viewBox='0 0 2... data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 2048 2048' %3E%3Cpath d='… — 200 — 0 B — 0 ms — datadata:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAASwAAACWCAYAAABkW7XSAAAQAElEQVR4AeycCXzVNbbHk3tbyl5AN…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAASwAAACWCAYAAABkW7XSAAAQAElEQVR4AeycCXzVNbbHk3tbyl5AN… — 200 — 0 B — 0 ms — datadata:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACGFjVEwAAAABAAAAAcMq2TYAAAANS…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACGFjVEwAAAABAAAAAcMq2TYAAAANS… — 200 — 0 B — 0 ms — datahttps://learn.microsoft.com/en-us/banners/index.jsonlearn.microsoft.com/en-us/banners/i... https://learn.microsoft.com/en-us/banners/index.json — 200 — 9.4 KiB — 14 ms — h2https://learn.microsoft.com/en-us/media/event-banners/banner-build-2026.pnglearn.microsoft.com/en-us/media/eve... https://learn.microsoft.com/en-us/media/event-banners/banner-build-2026.png — 200 — 62.0 KiB — 14 ms — h2https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/docons.e9637cb.7a2385d0.woff2learn.microsoft.com/static/assets/0... https://learn.microsoft.com/static/assets/0.4.03393.7734-e9637cbf/styles/docons.e9637cb.7a2385d0.woff2 — 200 — 24.1 KiB — 31 ms — h2https://learn.microsoft.com/static/third-party/SegoeUIVariable/SegoeUI-VF.ttflearn.microsoft.com/static/third-pa... https://learn.microsoft.com/static/third-party/SegoeUIVariable/SegoeUI-VF.ttf — 200 — 1.0 MiB — 48 ms — h2https://learn.microsoft.com/static/third-party/SegoeUIWeb/1.01.206/SegoeUI-Roman-VF_web.woff2learn.microsoft.com/static/third-pa... https://learn.microsoft.com/static/third-party/SegoeUIWeb/1.01.206/SegoeUI-Roman-VF_web.woff2 — 200 — 116.3 KiB — 49 ms — h2https://learn.microsoft.com/media/common/ai-microchip.svglearn.microsoft.com/media/common/ai... https://learn.microsoft.com/media/common/ai-microchip.svg — 302 — 1.8 KiB — 129 ms — h2https://learn.microsoft.com/media/logos/logo_azure.svglearn.microsoft.com/media/logos/log... https://learn.microsoft.com/media/logos/logo_azure.svg — 302 — 1.8 KiB — 139 ms — h2https://learn.microsoft.com/media/logos/logo_copilot.svglearn.microsoft.com/media/logos/log... https://learn.microsoft.com/media/logos/logo_copilot.svg — 302 — 1.8 KiB — 383 ms — h2https://learn.microsoft.com/media/learn/instructor-led-badge.svglearn.microsoft.com/media/learn/ins... https://learn.microsoft.com/media/learn/instructor-led-badge.svg — 302 — 1.8 KiB — 139 ms — h2https://learn.microsoft.com/training/achievements/generic-badge.svglearn.microsoft.com/training/achiev... https://learn.microsoft.com/training/achievements/generic-badge.svg — 302 — 1.8 KiB — 139 ms — h2https://learn.microsoft.com/media/home-and-directory/icon-azure-cloud.svglearn.microsoft.com/media/home-and-... https://learn.microsoft.com/media/home-and-directory/icon-azure-cloud.svg — 302 — 1.8 KiB — 160 ms — h2https://learn.microsoft.com/favicon.icolearn.microsoft.com/favicon.ico https://learn.microsoft.com/favicon.ico — 200 — 2.4 KiB — 13 ms — h2https://learn.microsoft.com/en-us/media/common/ai-microchip.svglearn.microsoft.com/en-us/media/com... https://learn.microsoft.com/en-us/media/common/ai-microchip.svg — 200 — 7.1 KiB — 60 ms — h2https://learn.microsoft.com/en-us/media/logos/logo_azure.svglearn.microsoft.com/en-us/media/log... https://learn.microsoft.com/en-us/media/logos/logo_azure.svg — 200 — 2.8 KiB — 89 ms — h2https://learn.microsoft.com/en-us/media/learn/instructor-led-badge.svglearn.microsoft.com/en-us/media/lea... https://learn.microsoft.com/en-us/media/learn/instructor-led-badge.svg — 200 — 5.9 KiB — 55 ms — h2https://learn.microsoft.com/en-us/training/achievements/generic-badge.svglearn.microsoft.com/en-us/training/... https://learn.microsoft.com/en-us/training/achievements/generic-badge.svg — 200 — 5.8 KiB — 21 ms — h2https://learn.microsoft.com/en-us/media/home-and-directory/icon-azure-cloud.svglearn.microsoft.com/en-us/media/hom... https://learn.microsoft.com/en-us/media/home-and-directory/icon-azure-cloud.svg — 200 — 37.3 KiB — 46 ms — h2https://learn.microsoft.com/en-us/media/logos/logo_copilot.svglearn.microsoft.com/en-us/media/log... https://learn.microsoft.com/en-us/media/logos/logo_copilot.svg — 200 — 2.9 KiB — 26 ms — h2https://learn.microsoft.com/akam/13/pixel_66ae903flearn.microsoft.com/akam/13/pixel_6... https://learn.microsoft.com/akam/13/pixel_66ae903f — 200 — 878 B — 9 ms — h2https://browser.events.data.microsoft.com/OneCollector/1.0/?cors=true&content-type=application/x-json-stream&w=0browser.events.data.microsoft.com/O... https://browser.events.data.microsoft.com/OneCollector/1.0/?cors=true&content-type=application/x-json-stream&w=0 — 200 — 0 B — 542 ms — h2https://browser.events.data.microsoft.com/OneCollector/1.0/?cors=true&content-type=application/x-json-stream&w=0browser.events.data.microsoft.com/O... https://browser.events.data.microsoft.com/OneCollector/1.0/?cors=true&content-type=application/x-json-stream&w=0 — 200 — 762 B — 498 ms — h2https://browser.events.data.microsoft.com/OneCollector/1.0/?cors=true&content-type=application/x-json-stream&w=0browser.events.data.microsoft.com/O... https://browser.events.data.microsoft.com/OneCollector/1.0/?cors=true&content-type=application/x-json-stream&w=0 — 200 — 234 B — 104 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 1748ms · 635KB · $23/mo
learn.microsoft.com
Other
Costly
Execution 627ms
Transfer 524 KB
Unused 69%
Monthly Cost $8/mo
learn.microsoft.com
Other
Costly
Execution 486ms
Transfer 10 KB
Monthly Cost $6/mo
Unattributable
Other
Costly
Execution 310ms
Transfer 0 KB
Monthly Cost $4/mo
learn.microsoft.com
Other
Costly
Execution 209ms
Transfer 27 KB
Monthly Cost $3/mo
js.monitor.azure.com
Other
Optional
Execution 116ms
Transfer 74 KB
Unused 40%
Monthly Cost $2/mo

These scripts may cost more than they're worth

  • learn.microsoft.com adds 627ms and costs ~$8/month
  • learn.microsoft.com adds 486ms and costs ~$6/month
  • Unattributable adds 310ms and costs ~$4/month
  • learn.microsoft.com adds 209ms and costs ~$3/month

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

learn.microsoft.com takes 627ms 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

69% of learn.microsoft.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

learn.microsoft.com takes 486ms 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 310ms 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

learn.microsoft.com takes 209ms 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