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https://www.freecodecamp.org

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
79
GRADE
C
FIX
3
REVIEW
1
PASS
10
INFO
2

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

Mobile Desktop
40
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
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.

3.94 s

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

13.24 s

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

1.21 s

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

0.000

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

5.09 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.

17.75 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
16
10 PASS 1 REVIEW 3 FIX
F
Page Weight Budget
Action
2.7 MB transferred, 51 requests
FIX
2.7 MB transferred, 51 requests
Warning::
Page weighs 9.6 MB (2.7 MB transferred)
Warning::
JavaScript is 2.4 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.4 MB
Info::
Fonts are 202 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 202 KB
Info::
51 HTTP requests
Info::
Estimated 0.58 g CO2 per page load
2.7 MB / 2.4 MB budget
2.7 MB transferred
51 requests
0.58 g CO2 per page load
JavaScript 2.4 MiB 86%
Fonts 202.2 KiB 7%
Images 90.2 KiB 3%
HTML 77.4 KiB 3%
Other 6.5 KiB 0%
Other 4.5 KiB 0%
Other 3.5 KiB 0%
Other 1.1 KiB 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

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

F
JS Execution Cost
Action
3611ms total JS execution
FIX
3611ms total JS execution
Warning::
https://www.freecodecamp.org/app-f5209401474dfc55e...: 1497ms CPU time
Warning::
https://www.freecodecamp.org/: 564ms CPU time
Warning::
Unattributable: 378ms CPU time
Warning::
https://www.freecodecamp.org/c8f7fe3b0e41be846d568...: 360ms CPU time
Warning::
https://js.stripe.com/v3: 322ms CPU time
Info::
Third-party scripts: 1136ms (31% of total)

Main Thread Breakdown

Script Evaluation 51% Script Parsing & Compilation 21% Other 15% Style & Layout 6%
ScriptTotalScriptingParse/CompileParty
https://www.freecodecamp.org/app-f5209401474dfc55e08f.js1497ms1214ms189ms1st
https://www.freecodecamp.org/564ms22ms3ms1st
Unattributable378ms13ms0ms3rd
https://www.freecodecamp.org/c8f7fe3b0e41be846d5687592cf2018ff6e22687-40d71bcd1644bb1c5dce.js360ms8ms351ms1st
https://js.stripe.com/v3322ms236ms80ms3rd
https://www.googletagmanager.com/gtag/js?id=G-SF1BGBDCNS&cx=c&gtm=4e6460273ms222ms38ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-57R6KJM&gtm_auth=&gtm_preview=&gtm_cookies_win=x163ms122ms39ms3rd
https://www.freecodecamp.org/7e3b4c62-ba61f723d90acd3f2bee.js54ms2ms48ms1st
F
JS Bundles
Action
17 scripts, 1.2 MB unused
FIX
17 scripts, 1.2 MB unused
Warning::
https://www.freecodecamp.org/c8f7fe3b0e41be846d568...: 725 KB unused (100%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.freecodecamp.org/app-f5209401474dfc55e...: 142 KB unused (30%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://js.stripe.com/v3: 141 KB unused (64%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.freecodecamp.org/7e3b4c62-ba61f723d90a...: 78 KB unused (60%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-SF1B...: 65 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.2 MB
1235 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.freecodecamp.org/c8f7fe3b0e41be846d5687592cf2018ff6e22687-40d71bcd1644bb1c5dce.js726 KB725 KB (100%)✓1st
https://www.freecodecamp.org/app-f5209401474dfc55e08f.js467 KB142 KB (30%)✓1st
https://js.stripe.com/v3220 KB141 KB (64%)✓3rd
https://www.freecodecamp.org/7e3b4c62-ba61f723d90acd3f2bee.js135 KB78 KB (60%)✓1st
https://www.googletagmanager.com/gtag/js?id=G-SF1BGBDCNS&cx=c&gtm=4e6460155 KB65 KB (42%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-57R6KJM&gtm_auth=&gtm_preview=&gtm_cookies_win=x123 KB62 KB (51%)✓3rd
https://www.freecodecamp.org/component---src-pages-index-tsx-593d70c38cd28a78f7ef.js40 KB21 KB (53%)✓1st
https://static.cloudflareinsights.com/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312451611 KB—✓3rd
https://www.freecodecamp.org/d82bff99d17dc59c45b6281a99a3ed0ccb6fc4cd-aed71431ef4b123bbb8f.js12 KB—✓1st
https://www.freecodecamp.org/webpack-runtime-a8251fda6df8e26fe320.js6 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

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

public, max-age=0, must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
A
Third-Party Impact
37% third-party, 0 ms blocking
PASS
37% third-party, 0 ms blocking
Info::
Third-party code accounts for 37% of page weight (1.0 MiB of 2.7 MiB)
Info::
Third-party blocking time is low (0 ms)
63%
37%
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+
Image Optimization
3 images, 0 KB saveable
PASS
3 images, 0 KB saveable
Info::
All images are well-optimized
3 images 90 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+
Font Loading
7 fonts (202 KB)
PASS
7 fonts (202 KB)
Info::
7 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

7

202 KB total

Render-blocking

0

of 7

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 12.0 s FCP 3.9 s LCP 13.2 shttps://www.freecodecamp.org/static/Lato-Regular-77ca2742388f408c3be7d0ec3e7dc392.woffLato-Regular-77ca274238... https://www.freecodecamp.org/static/Lato-Regular-77ca2742388f408c3be7d0ec3e7dc392.woff — 37.3 KiB — 0 ms — font-display: swaphttps://www.freecodecamp.org/static/Lato-Light-91308c0216b40aad16036f1394b98237.woffLato-Light-91308c0216b4... https://www.freecodecamp.org/static/Lato-Light-91308c0216b40aad16036f1394b98237.woff — 35.0 KiB — 0 ms — font-display: swaphttps://www.freecodecamp.org/static/Lato-Bold-ba3a83adcb94357fc42f762985e4d3df.woffLato-Bold-ba3a83adcb943... https://www.freecodecamp.org/static/Lato-Bold-ba3a83adcb94357fc42f762985e4d3df.woff — 36.5 KiB — 0 ms — font-display: swaphttps://www.freecodecamp.org/static/Hack-ZeroSlash-Regular-f67447de5dc6604f538786bd55ac6019.woffHack-ZeroSlash-Regular-... https://www.freecodecamp.org/static/Hack-ZeroSlash-Regular-f67447de5dc6604f538786bd55ac6019.woff — 29.3 KiB — 0 ms — font-display: swaphttps://www.freecodecamp.org/static/Hack-ZeroSlash-Bold-c8ea19a8461596cf1a6a2ad08bebcf8e.woffHack-ZeroSlash-Bold-c8e... https://www.freecodecamp.org/static/Hack-ZeroSlash-Bold-c8ea19a8461596cf1a6a2ad08bebcf8e.woff — 29.7 KiB — 0 ms — font-display: swaphttps://www.freecodecamp.org/static/Hack-ZeroSlash-Italic-678bc16b550480d5a3c5c76dbf8c5fb9.woffHack-ZeroSlash-Italic-6... https://www.freecodecamp.org/static/Hack-ZeroSlash-Italic-678bc16b550480d5a3c5c76dbf8c5fb9.woff — 34.3 KiB — 0 ms — font-display: swaphttps://www.freecodecamp.org/static/Lato-Bold-ba3a83adcb94357fc42f762985e4d3df.woffLato-Bold-ba3a83adcb943... https://www.freecodecamp.org/static/Lato-Bold-ba3a83adcb94357fc42f762985e4d3df.woff — 0 B — 0 ms — font-display: swap
Lato-Regular-77ca274238... woff swap
Size 37 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
Lato-Light-91308c0216b4... woff swap
Size 35 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
Lato-Bold-ba3a83adcb943... woff swap
Size 37 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
Hack-ZeroSlash-Regular-... woff swap
Size 29 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
Hack-ZeroSlash-Bold-c8e... woff swap
Size 30 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
Hack-ZeroSlash-Italic-6... woff swap
Size 34 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
Lato-Bold-ba3a83adcb943... woff swap
Size 0 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
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 ~61 KB and ~122 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
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
51 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
31% of JavaScript execution is third-party
First-party Third-party 1136ms · 497KB · $4/mo
Unattributable
Other
Costly
Execution 378ms
Transfer 0 KB
Monthly Cost $1/mo
Stripe
Payment
Essential
Execution 322ms
Transfer 220 KB
Unused 64%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Costly
Execution 273ms
Transfer 155 KB
Unused 42%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 163ms
Transfer 123 KB
Unused 51%
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 378ms and costs ~$1/month
  • Google Tag Manager adds 273ms and costs ~$1/month

Unattributable takes 378ms 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 Stripe'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

Google Tag Manager takes 273ms 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

51% of Google Tag Manager'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

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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