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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
70
GRADE
C
FIX
4
REVIEW
2
PASS
6
INFO
2

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

Mobile Desktop
42
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
84
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.
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.

944 ms

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

3.70 s

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

572 ms

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

0.143

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

3.25 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.

5.65 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
6 PASS 2 REVIEW 4 FIX
F
Page Weight Budget
Action
5.1 MB transferred, 153 requests
FIX
5.1 MB transferred, 153 requests
Critical::
Page weighs 16.6 MB (5.1 MB transferred)
Warning::
JavaScript is 2.1 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.1 MB
Warning::
Images are 1.6 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.6 MB
Info::
Fonts are 1.1 MB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 1.1 MB
Warning::
153 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.1 g CO2 per page load
5.1 MB / 2.4 MB budget
5.1 MB transferred
153 requests
1.1 g CO2 per page load
JavaScript 2.1 MiB 42%
Images 1.6 MiB 32%
Fonts 1.1 MiB 22%
Other 71.1 KiB 1%
HTML 63.3 KiB 1%
CSS 54.3 KiB 1%
Other 18.9 KiB 0%
Other 1.6 KiB 0%
Other 545 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over 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

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

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

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

D
Third-Party Impact
Action
97% third-party, 0 ms blocking
FIX
97% third-party, 0 ms blocking
Warning::
Third-party code accounts for 97% of page weight (4.9 MiB of 5.1 MiB)
Info::
Third-party blocking time is low (0 ms)
97%
First-party Third-party
D
JS Execution Cost
Action
3272ms total JS execution
FIX
3272ms total JS execution
Warning::
https://frontends.udemycdn.com/frontends-homepage/...: 1395ms CPU time
Warning::
https://frontends.udemycdn.com/frontends-homepage/...: 377ms CPU time
Warning::
https://cdn.cookielaw.org/consent/25ab360c-347c-4a...: 342ms CPU time
Warning::
https://frontends.udemycdn.com/frontends-homepage/...: 314ms CPU time
Info::
https://www.udemy.com/: 232ms CPU time
Warning::
Third-party scripts: 2952ms (90% of total)

Main Thread Breakdown

Script Evaluation 61% Script Parsing & Compilation 11% Other 11% Garbage Collection 7% Style & Layout 6%
ScriptTotalScriptingParse/CompileParty
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/pages/lohp-b6ea9acfc109d4a6.js1395ms1133ms2ms3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/pages/_app-b224ea5cbb64cb36.js377ms221ms32ms3rd
https://cdn.cookielaw.org/consent/25ab360c-347c-4a85-8b93-1e0326234b75/OtAutoBlock.js342ms86ms256ms3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/7X7PJwEDfA63XeUwLNJKc/_buildManifest.js314ms268ms0ms3rd
https://www.udemy.com/232ms19ms1ms1st
Unattributable188ms8ms0ms3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/649-6254f0927693bd7b.js181ms76ms15ms3rd
https://www.udemy.com/cdn-cgi/challenge-platform/scripts/jsd/main.js88ms80ms1ms1st
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/framework-8b7974553b1447ee.js80ms68ms8ms3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/1edf0483.9dfe51f2fe978bc8.js75ms69ms4ms3rd
F
JS Bundles
Action
23 scripts, 503 KB unused
FIX
23 scripts, 503 KB unused
Warning::
https://frontends.udemycdn.com/frontends-homepage/...: 203 KB unused (63%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.cookielaw.org/scripttemplates/202603.1...: 107 KB unused (83%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://accounts.google.com/gsi/client: 69 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://frontends.udemycdn.com/frontends-homepage/...: 63 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://frontends.udemycdn.com/frontends-homepage/...: 40 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 503 KB
503 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/pages/_app-b224ea5cbb64cb36.js322 KB203 KB (63%)✓3rd
https://cdn.cookielaw.org/scripttemplates/202603.1.0/otBannerSdk.js130 KB107 KB (83%)✓3rd
https://accounts.google.com/gsi/client94 KB69 KB (74%)✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/649-6254f0927693bd7b.js154 KB63 KB (41%)✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/163-715a7e94cdaaa4ee.js93 KB40 KB (43%)✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/1edf0483.9dfe51f2fe978bc8.js51 KB22 KB (43%)✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/28d6da4e-51830bc1bc67c125.js2 KB—✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/7X7PJwEDfA63XeUwLNJKc/_buildManifest.js1 KB—✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/6f804df0-ce3e93b723b6385a.js2 KB—✓3rd
https://frontends.udemycdn.com/frontends-homepage/_next/static/chunks/48512dd7-e4050b33c5a5dc02.js1 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

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

C
Image Optimization
Action
42 images, 0 KB saveable
REVIEW
42 images, 0 KB saveable
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/2pNyD... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/6100015_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/5655756_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/5238734_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/3Yzfv... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/6112535_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/23Xnh... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/2196488_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://frontends.udemycdn.com/frontends-homepage/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://s.udemycdn.com/career-academies/product-ca... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://s.udemycdn.com/career-academies/product-ca... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://s.udemycdn.com/career-academies/product-ca... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/3E0eI... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/2tQm6... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/7guDR... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/1UUVZ... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cms-images.udemycdn.com/96883mtakkm8/1GoAi... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/2776760_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://frontends.udemycdn.com/frontends-homepage/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/6566789_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/3142166_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://img-c.udemycdn.com/course/750x422/6082775_... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://frontends.udemycdn.com/staticx/udemy/image... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://frontends.udemycdn.com/frontends-homepage/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
42 images 1.6 MB
0 oversized -0 KB
17 legacy format
25 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

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

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

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

Set explicit width and height to prevent CLS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

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

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

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

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

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

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

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
HTTP Caching
s-maxage=14400, stale-while-revalidate
REVIEW
s-maxage=14400, stale-while-revalidate
Info::
Cache-Control header is set
Got: s-maxage=14400, stale-while-revalidate
Info::
CDN TTL: 4 hours (s-maxage=14400)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

s-maxage=14400, stale-while-revalidate

DirectiveValueMeaning
s-maxage14400CDN caches for 4 hours
stale-while-revalidate—Serve stale while revalidating
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
6 fonts (1150 KB)
PASS
6 fonts (1150 KB)
Info::
6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

6

1150 KB total

Render-blocking

0

of 6

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 944 ms LCP 3.7 shttps://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Light-v1.woff2Udemy-Sans-Light-v1.woff2 https://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Light-v1.woff2 — 34.5 KiB — 0 ms — font-display: swaphttps://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Regular-v1.woff2Udemy-Sans-Regular-v1.w... https://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Regular-v1.woff2 — 35.6 KiB — 0 ms — font-display: swaphttps://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Medium-v1.woff2Udemy-Sans-Medium-v1.woff2 https://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Medium-v1.woff2 — 35.6 KiB — 0 ms — font-display: swaphttps://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Bold-v1.woff2Udemy-Sans-Bold-v1.woff2 https://frontends.udemycdn.com/thesis/fonts/Udemy-Sans-Bold-v1.woff2 — 35.8 KiB — 0 ms — font-display: swaphttps://frontends.udemycdn.com/thesis/fonts/Vazirmatn-Light.woff2Vazirmatn-Light.woff2 https://frontends.udemycdn.com/thesis/fonts/Vazirmatn-Light.woff2 — 50.4 KiB — 0 ms — font-display: swaphttps://frontends.udemycdn.com/thesis/fonts/noto-sans-jp-japanese-400-normal.woff2noto-sans-jp-japanese-4... https://frontends.udemycdn.com/thesis/fonts/noto-sans-jp-japanese-400-normal.woff2 — 957.6 KiB — 0 ms — font-display: swap
Udemy-Sans-Light-v1.woff2 woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Udemy-Sans-Regular-v1.w... woff2 swap
Size 36 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Udemy-Sans-Medium-v1.woff2 woff2 swap
Size 36 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Udemy-Sans-Bold-v1.woff2 woff2 swap
Size 36 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Vazirmatn-Light.woff2 woff2 swap
Size 50 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
noto-sans-jp-japanese-4... woff2 swap
Size 958 KB
Load time 0 ms
Start 0 ms
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 ~479 KB and ~958 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+
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
153 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
90% of JavaScript execution is third-party
First-party Third-party 2952ms · 1716KB · $39/mo
frontends.udemycdn.com
Other
Costly
Execution 1395ms
Transfer 26 KB
Monthly Cost $19/mo
frontends.udemycdn.com
Other
Costly
Execution 377ms
Transfer 322 KB
Unused 63%
Monthly Cost $5/mo
OneTrust
Consent
Essential
Execution 342ms
Transfer 1119 KB
Monthly Cost $5/mo
frontends.udemycdn.com
Other
Costly
Execution 314ms
Transfer 1 KB
Monthly Cost $4/mo
Unattributable
Other
Optional
Execution 188ms
Transfer 0 KB
Monthly Cost $2/mo
frontends.udemycdn.com
Other
Optional
Execution 181ms
Transfer 154 KB
Unused 41%
Monthly Cost $2/mo
frontends.udemycdn.com
Other
Optional
Execution 80ms
Transfer 42 KB
Monthly Cost $1/mo
frontends.udemycdn.com
Other
Optional
Execution 75ms
Transfer 51 KB
Unused 43%
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • frontends.udemycdn.com adds 1395ms and costs ~$19/month
  • frontends.udemycdn.com adds 377ms and costs ~$5/month
  • frontends.udemycdn.com adds 314ms and costs ~$4/month

90% 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

frontends.udemycdn.com takes 1395ms 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

frontends.udemycdn.com takes 377ms 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

63% of frontends.udemycdn.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

frontends.udemycdn.com takes 314ms 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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