Performance
· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
892 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.26 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
17 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.007
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
892 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.
1.56 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 sFPage Weight BudgetAction3.3 MB transferred, 48 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
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.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction48 resources · 3.3 MB · 111 KB savings availableFIX
~111.0 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 48 resources | 3.3 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization28 images, 0 KB saveableREVIEW
BJS Execution Cost581ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.mediapart.fr/ | 352ms | 7ms | 1ms | 3rd |
| https://www.mediapart.fr/assets/build/default/front/nouvelle_formule/js/home.44b0c0ec27d7a16e.js | 161ms | 51ms | 0ms | 3rd |
| Unattributable | 67ms | 1ms | 0ms | 3rd |
BJS Bundles5 scripts, 111 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.mediapart.fr/assets/build/default/front/nouvelle_formule/js/vendors.f4ea60fdad8a96e7.js | 81 KB | 60 KB (75%) | ✓ | 3rd |
| https://targetemsecure.blob.core.windows.net/84e5c880-8719-4773-8dad-7c722eb16350/84e5c880871947738dad7c722eb16350_2_1771968345.js | 45 KB | 30 KB (68%) | ✓ | 3rd |
| https://www.mediapart.fr/assets/build/default/front/nouvelle_formule/js/commons.23df507ff2f81a66.js | 42 KB | 20 KB (49%) | ✓ | 3rd |
| https://targetemsecure.blob.core.windows.net/84e5c880-8719-4773-8dad-7c722eb16350/84e5c880871947738dad7c722eb16350_1.js | 5 KB | — | ✓ | 3rd |
| https://www.mediapart.fr/assets/build/default/front/nouvelle_formule/js/home.44b0c0ec27d7a16e.js | 0 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading7 fonts (250 KB)PASS
Web fonts
7
250 KB total
Render-blocking
0
of 7
Dominant font-display
swap
Most common across fonts
Font loading timeline
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 CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall48 requests over 816msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.mediapart.fr www.mediapart.fr | Other | 352ms | 172 KB | — | €4/mo | Costly |
www.mediapart.fr www.mediapart.fr | Other | 161ms | 0 KB | — | €2/mo | Optional |
Unattributable Unattributable | Other | 67ms | 0 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.mediapart.fr adds 352ms and costs ~€4/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
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.mediapart.fr takes 352ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev