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https://www.education.gouv.fr

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
85
GRADE
B
FIX
2
REVIEW
3
PASS
7
INFO
2

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

Mobile Desktop
94
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.
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.

663 ms

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

1.58 s

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

10 ms

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

0.006

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

959 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.70 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
2.4 MB transferred, 56 requests
FIX
2.4 MB transferred, 56 requests
Info::
Page weighs 4.4 MB (2.4 MB transferred)
Warning::
Images are 1.9 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.9 MB
Info::
56 HTTP requests
Info::
Estimated 0.51 g CO2 per page load
2.4 MB / 2.4 MB budget
2.4 MB transferred
56 requests
0.51 g CO2 per page load
Images 1.9 MiB 78%
JavaScript 213.4 KiB 9%
Fonts 166.3 KiB 7%
CSS 151.9 KiB 6%
HTML 16.1 KiB 1%
Other 3.0 KiB 0%
Other 967 B 0%
Other 480 B 0%
0 2.4 MB 4.9 MB
Approaching limit

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

D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
max-age0Cache for 0 seconds
no-store—Never cache this response
no-cache—Cache but always revalidate first
must-revalidate—Must recheck with server after expiry
post-check0
pre-check0
C
Image Optimization
Action
31 images, 0 KB saveable
REVIEW
31 images, 0 KB saveable
Warning::
https://www.education.gouv.fr/sites/default/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.education.gouv.fr/sites/default/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.education.gouv.fr/sites/default/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.education.gouv.fr/sites/default/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.education.gouv.fr/sites/default/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.education.gouv.fr/sites/default/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
31 images 1.9 MB
0 oversized -0 KB
19 legacy format
6 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

B
JS Execution Cost
643ms total JS execution
REVIEW
643ms total JS execution
Info::
https://www.education.gouv.fr/: 191ms CPU time
Info::
Unattributable: 188ms CPU time
Info::
https://www.education.gouv.fr/cdn-cgi/challenge-pl...: 140ms CPU time
Info::
https://www.education.gouv.fr/libraries/dsfr/dist/...: 123ms CPU time
Info::
Third-party scripts: 188ms (29% of total)

Main Thread Breakdown

Script Evaluation 38% Other 33% Style & Layout 17% Parse HTML & CSS 4% Rendering 4%
ScriptTotalScriptingParse/CompileParty
https://www.education.gouv.fr/191ms35ms1ms1st
Unattributable188ms2ms0ms3rd
https://www.education.gouv.fr/cdn-cgi/challenge-platform/scripts/jsd/main.js140ms136ms0ms1st
https://www.education.gouv.fr/libraries/dsfr/dist/dsfr.module.js?v=1.x123ms60ms0ms1st
C
JS Bundles
Action
10 scripts, 75 KB unused
REVIEW
10 scripts, 75 KB unused
Warning::
https://www.education.gouv.fr/sites/default/files/...: 30 KB unused (61%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.education.gouv.fr/libraries/tarteaucit...: 24 KB unused (73%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.education.gouv.fr/libraries/tarteaucit...: unminified — 9 KB could be saved
Warning::
https://www.education.gouv.fr/sites/default/files/...: 22 KB unused (57%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.education.gouv.fr/libraries/dsfr/dist/...: unminified — 8 KB could be saved
Info::
Total unused JavaScript: 75 KB
75 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.education.gouv.fr/sites/default/files/js/js_tzoLcjdeSzPZwn63KF-tyOCA_bDWuZUo80sYsW6aoT8.js?scope=footer&delta=2&language=fr&theme=edugouv_dsfr&include=eJxVjOEKAyEMg1_oPB9JPO1KobZi68C3H9vY8P6E5EtI0QGxaOsqIG6nZ6nQUrXHCMGJIeHQ2Q-oE3U-P0Us01zbsW3jWxIJ-Y0i65U5mC8mwV-FtY-4-Z2nLJmXU7Hv5T--ABorQts49 KB30 KB (61%)✓1st
https://www.education.gouv.fr/libraries/tarteaucitron.js/tarteaucitron.services.js?v=2022032233 KB24 KB (73%)✗1st
https://www.education.gouv.fr/sites/default/files/js/js_WfPPp7sH-1ECmhNZVUIC56qjeFlH4GbDtBfWjYg9VPI.js?scope=footer&delta=0&language=fr&theme=edugouv_dsfr&include=eJxVjOEKAyEMg1_oPB9JPO1KobZi68C3H9vY8P6E5EtI0QGxaOsqIG6nZ6nQUrXHCMGJIeHQ2Q-oE3U-P0Us01zbsW3jWxIJ-Y0i65U5mC8mwV-FtY-4-Z2nLJmXU7Hv5T--ABorQts39 KB22 KB (57%)✓1st
https://www.education.gouv.fr/core/assets/vendor/modernizr/modernizr.min.js?v=3.11.73 KB—✓1st
https://www.education.gouv.fr/libraries/dsfr/dist/dsfr.module.js?v=1.x37 KB—✗1st
https://www.education.gouv.fr/libraries/dsfr/dist/analytics/analytics.module.js?td4vez22 KB—✗1st
https://www.education.gouv.fr/libraries/tarteaucitron.js/lang/tarteaucitron.fr.js?v=202203222 KB—✓1st
https://www.education.gouv.fr/cdn-cgi/challenge-platform/h/b/scripts/jsd/625261456364/main.js?12 KB—✓1st
https://wrhv.education.gouv.fr/fuF559.js?214 KB—✓3rd
https://wrhv.education.gouv.fr/col571a/-/1021428883?url=https%3A%2F%2Fwww.education.gouv.fr%2F&sd=24&ss=800x600&fra=0&evariant=2-4&3 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

A+
Third-Party Impact
1% third-party, 0 ms blocking
PASS
1% third-party, 0 ms blocking
Info::
Third-party code accounts for 1% of page weight (18.1 KiB of 2.4 MiB)
Info::
Third-party blocking time is low (0 ms)
99%
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+
Font Loading
4 fonts (166 KB)
PASS
4 fonts (166 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

166 KB total

Render-blocking

0

of 4

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 FCP 663 ms LCP 1.6 shttps://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Regular.woff2Marianne-Regular.woff2 https://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Regular.woff2 — 40.5 KiB — 0 ms — font-display: swaphttps://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Bold.woff2Marianne-Bold.woff2 https://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Bold.woff2 — 41.3 KiB — 0 ms — font-display: swaphttps://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Regular_Italic.woff2Marianne-Regular_Italic... https://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Regular_Italic.woff2 — 43.4 KiB — 0 ms — font-display: swaphttps://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Medium.woff2Marianne-Medium.woff2 https://www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Medium.woff2 — 41.1 KiB — 0 ms — font-display: swap
Marianne-Regular.woff2 woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Marianne-Bold.woff2 woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Marianne-Regular_Italic... woff2 swap
Size 43 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Marianne-Medium.woff2 woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
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)
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
56 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
29% of JavaScript execution is third-party
First-party Third-party 188ms · 0KB · €2/mo
Unattributable
Other
Optional
Execution 188ms
Transfer 0 KB
Monthly Cost €2/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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