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https://nuget.org

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
88
GRADE
B
FIX
2
REVIEW
4
PASS
9
INFO
2

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

Mobile Desktop
57
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.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

3.13 s

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

4.75 s

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

88 ms

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

0.399

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

3.85 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.

6.02 s

Page Load Progression

498 ms
995 ms
1.5 s
2.0 s
2.5 s
3.0 s
3.5 s
4.0 s
Checks
17
9 PASS 4 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 (672.2 KiB of 673.8 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
Info::
All images are well-optimized
4 images 12 KB
0 oversized -0 KB
4 legacy format
0 missing dimensions CLS risk
C
JS Execution Cost
Action
1315ms total JS execution
REVIEW
1315ms total JS execution
Warning::
https://www.nuget.org/Scripts/gallery/site.min.js?...: 515ms CPU time
Warning::
https://www.nuget.org/: 428ms CPU time
Warning::
Unattributable: 308ms CPU time
Info::
https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-co...: 65ms CPU time
Warning::
Third-party scripts: 1315ms (100% of total)

Main Thread Breakdown

Other 38% Script Evaluation 30% Style & Layout 16% Script Parsing & Compilation 7% Parse HTML & CSS 5% Rendering 3%
ScriptTotalScriptingParse/CompileParty
https://www.nuget.org/Scripts/gallery/site.min.js?v=9352ShibzZ-oY8G2paDIJFoRoTrWghNF7YlXi2tc4d01515ms361ms49ms3rd
https://www.nuget.org/428ms16ms3ms3rd
Unattributable308ms9ms0ms3rd
https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.js65ms21ms43ms3rd
B
JS Bundles
3 scripts, 62 KB unused
REVIEW
3 scripts, 62 KB unused
Warning::
https://www.nuget.org/Scripts/gallery/site.min.js?...: 62 KB unused (64%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 62 KB
62 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.nuget.org/Scripts/gallery/site.min.js?v=9352ShibzZ-oY8G2paDIJFoRoTrWghNF7YlXi2tc4d0198 KB62 KB (64%)✓3rd
https://wcpstatic.microsoft.com/mscc/lib/v2/wcp-consent.js274 KB—✓3rd
https://www.nuget.org/Scripts/gallery/page-home.min.js?v=49avs5MpLWP-MC3EThOG_qqrwX9Dm7HC9pEs04f_DmU13 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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
674 KB transferred, 17 requests
PASS
674 KB transferred, 17 requests
Info::
Page weighs 1.3 MB (674 KB transferred)
Info::
17 HTTP requests
Info::
Estimated 0.14 g CO2 per page load
674 KB / 2.4 MB budget
674 KB transferred
17 requests
0.14 g CO2 per page load
JavaScript 374.2 KiB 56%
Fonts 193.9 KiB 29%
CSS 69.3 KiB 10%
Other 17.9 KiB 3%
Images 11.6 KiB 2%
HTML 5.4 KiB 1%
Other 1.7 KiB 0%
0 2.4 MB 4.9 MB
Under budget
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
1 fonts (194 KB)
PASS
1 fonts (194 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

194 KB total

Render-blocking

0

of 1

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 3.1 s LCP 4.7 shttps://res-1.cdn.office.net/files/fabric-cdn-prod_20221201.001/assets/icons/fabricmdl2icons-3.70.wofffabricmdl2icons-3.70.woff https://res-1.cdn.office.net/files/fabric-cdn-prod_20221201.001/assets/icons/fabricmdl2icons-3.70.woff — 193.9 KiB — 33 ms — font-display: swap
fabricmdl2icons-3.70.woff woff swap
Size 194 KB
Load time 33 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
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 ~155 KB and ~310 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
Page Weight Inventory
17 resources · 674 KB · 62 KB savings available
PASS
17 resources · 674 KB · 62 KB savings available
Info::
Within 1MB page-weight target
Got: 674 KB
Info::
~62 KB of savings available
Warning::
13 third-party resources (100% of weight)
Info::
1 resources over 200KB
17 resources · 673.8 KiB · 13 third-party Within 1MB page-weight target
JavaScript 56% · 374.2 KiB
Font 29% · 193.9 KiB
CSS 10% · 69.3 KiB
Image 4% · 27.8 KiB
Document 1% · 7.0 KiB
Other 0% · 1.7 KiB

~61.8 KiB of savings available

Remove unused JavaScript: 61.8 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
Network Waterfall
17 requests over 1939ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 3.1 s LCP 4.7 shttps://nuget.org// https://nuget.org/ — 301 — 596 B — 315 ms — http/1.1https://www.nuget.org/www.nuget.org/ https://www.nuget.org/ — 200 — 5.4 KiB — 554 ms — http/1.1https://www.nuget.org/Content/gallery/css/site.min.css?v=1na5Q3HPVSkugniYsNxjmE134E1C4dpzFOT5rmDYA-E1www.nuget.org/Content/gallery/css/s... https://www.nuget.org/Content/gallery/css/site.min.css?v=1na5Q3HPVSkugniYsNxjmE134E1C4dpzFOT5rmDYA-E1 — 200 — 32.6 KiB — 425 ms — http/1.1https://www.nuget.org/Content/gallery/css/bootstrap.min.csswww.nuget.org/Content/gallery/css/b... https://www.nuget.org/Content/gallery/css/bootstrap.min.css — 200 — 36.7 KiB — 614 ms — http/1.1https://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 — 226 ms — h2https://www.nuget.org/Scripts/gallery/site.min.js?v=9352ShibzZ-oY8G2paDIJFoRoTrWghNF7YlXi2tc4d01www.nuget.org/Scripts/gallery/site.... https://www.nuget.org/Scripts/gallery/site.min.js?v=9352ShibzZ-oY8G2paDIJFoRoTrWghNF7YlXi2tc4d01 — 200 — 97.8 KiB — 780 ms — http/1.1https://www.nuget.org/Scripts/gallery/page-home.min.js?v=49avs5MpLWP-MC3EThOG_qqrwX9Dm7HC9pEs04f_DmU1www.nuget.org/Scripts/gallery/page-... https://www.nuget.org/Scripts/gallery/page-home.min.js?v=49avs5MpLWP-MC3EThOG_qqrwX9Dm7HC9pEs04f_DmU1 — 200 — 2.6 KiB — 189 ms — http/1.1https://nuget.org/Content/gallery/img/book-open-icon.svg/Content/gallery/img/book-open-icon... https://nuget.org/Content/gallery/img/book-open-icon.svg — 301 — 352 B — 101 ms — http/1.1https://nuget.org/Content/gallery/img/search-icon.svg/Content/gallery/img/search-icon.sv... https://nuget.org/Content/gallery/img/search-icon.svg — 301 — 349 B — 107 ms — http/1.1https://nuget.org/Content/gallery/img/rocket-icon.svg/Content/gallery/img/rocket-icon.sv... https://nuget.org/Content/gallery/img/rocket-icon.svg — 301 — 349 B — 201 ms — http/1.1https://www.nuget.org/Content/gallery/img/nuget-lockup-dark-fill.svgwww.nuget.org/Content/gallery/img/n... https://www.nuget.org/Content/gallery/img/nuget-lockup-dark-fill.svg — 200 — 4.2 KiB — 203 ms — http/1.1https://res-1.cdn.office.net/files/fabric-cdn-prod_20221201.001/assets/icons/fabricmdl2icons-3.70.woffres-1.cdn.office.net/files/fabric-c... https://res-1.cdn.office.net/files/fabric-cdn-prod_20221201.001/assets/icons/fabricmdl2icons-3.70.woff — 200 — 193.9 KiB — 33 ms — h2https://www.nuget.org/Content/gallery/img/book-open-icon.svgwww.nuget.org/Content/gallery/img/b... https://www.nuget.org/Content/gallery/img/book-open-icon.svg — 200 — 2.3 KiB — 112 ms — http/1.1https://www.nuget.org/Content/gallery/img/search-icon.svgwww.nuget.org/Content/gallery/img/s... https://www.nuget.org/Content/gallery/img/search-icon.svg — 200 — 2.1 KiB — 108 ms — http/1.1https://www.nuget.org/Content/gallery/img/rocket-icon.svgwww.nuget.org/Content/gallery/img/r... https://www.nuget.org/Content/gallery/img/rocket-icon.svg — 200 — 2.9 KiB — 107 ms — http/1.1https://www.nuget.org/stats/totalswww.nuget.org/stats/totals https://www.nuget.org/stats/totals — 200 — 1.7 KiB — 107 ms — http/1.1https://www.nuget.org/favicon.icowww.nuget.org/favicon.ico https://www.nuget.org/favicon.ico — 200 — 16.2 KiB — 207 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
100% of JavaScript execution is third-party
First-party Third-party 1315ms · 377KB · $17/mo
www.nuget.org
Other
Costly
Execution 515ms
Transfer 98 KB
Unused 64%
Monthly Cost $7/mo
www.nuget.org
Other
Costly
Execution 428ms
Transfer 5 KB
Monthly Cost $6/mo
Unattributable
Other
Costly
Execution 308ms
Transfer 0 KB
Monthly Cost $4/mo
wcpstatic.microsoft.com
Other
Optional
Execution 65ms
Transfer 274 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • www.nuget.org adds 515ms and costs ~$7/month
  • www.nuget.org adds 428ms and costs ~$6/month
  • Unattributable adds 308ms and costs ~$4/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

www.nuget.org takes 515ms 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

64% of www.nuget.org'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

www.nuget.org takes 428ms 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 308ms 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.

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