Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

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

Mobile Desktop

Performance

Accessibility

Best Practices

100

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.05 s

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

1.55 s

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

288 ms

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

0.001

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

1.79 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.

3.58 s

Page Load Progression

468 ms

936 ms

1.4 s

1.9 s

2.3 s

2.8 s

3.3 s

3.7 s

Checks

5 PASS 3 REVIEW 5 FIX

Page Weight Budget

Action

3.1 MB transferred, 308 requests

FIX

3.1 MB transferred, 308 requests

Page weighs 6.2 MB (3.1 MB transferred)

Images are 2.1 MB — compress or use modern formats

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

Got: 2.1 MB

JavaScript is 688 KB — consider code splitting or lazy loading

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Got: 688 KB

308 HTTP requests — consider bundling or reducing

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

Estimated 0.65 g CO2 per page load

3.1 MB transferred

308 requests

0.65 g CO2 per page load

Images 2.1 MiB 67%

JavaScript 688.1 KiB 22%

HTML 221.1 KiB 7%

CSS 75.5 KiB 2%

Fonts 38.5 KiB 1%

Other 2.4 KiB 0%

Other 1.7 KiB 0%

Other 1.6 KiB 0%

Other 228 B 0%

0 2.4 MB 4.9 MB

Over budget

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

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

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

Third-Party Impact

Action

100% third-party, 0 ms blocking

FIX

100% third-party, 0 ms blocking

Third-party code accounts for 100% of page weight (3.1 MiB of 3.1 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

JS Execution Cost

Action

2676ms total JS execution

FIX

2676ms total JS execution

https://www.radiofrance.fr/_app/immutable/chunks/C...: 794ms CPU time

https://www.radiofrance.fr/: 775ms CPU time

Unattributable: 426ms CPU time

https://s.go-mpulse.net/boomerang/WEG5J-NEMNG-DBMM...: 381ms CPU time

https://www.radiofrance.fr/_app/immutable/chunks/C...: 115ms CPU time

Third-party scripts: 2676ms (100% of total)

Main Thread Breakdown

Script Evaluation 40% Other 27% Style & Layout 19% Rendering 5% Parse HTML & CSS 4% Garbage Collection 3%

Script	Total	Scripting	Parse/Compile	Party
https://www.radiofrance.fr/_app/immutable/chunks/CuarxdrD.js	794ms	604ms	0ms	3rd
https://www.radiofrance.fr/	775ms	45ms	36ms	3rd
Unattributable	426ms	49ms	0ms	3rd
https://s.go-mpulse.net/boomerang/WEG5J-NEMNG-DBMMB-XH7VN-GNXVV	381ms	246ms	6ms	3rd
https://www.radiofrance.fr/_app/immutable/chunks/Ci0K-xwM.js	115ms	76ms	0ms	3rd
https://sdk.privacy-center.org/sdk/22ecd6bfac93de604efec0b75b2c796ee1675f92/modern/ui-web-fr-web.22ecd6bfac93de604efec0b75b2c796ee1675f92.js	94ms	26ms	8ms	3rd
https://sdk.privacy-center.org/sdk/22ecd6bfac93de604efec0b75b2c796ee1675f92/modern/sdk.22ecd6bfac93de604efec0b75b2c796ee1675f92.js	90ms	74ms	12ms	3rd

Page Weight Inventory

Action

308 resources · 3.1 MB · 146 KB savings available

FIX

308 resources · 3.1 MB · 146 KB savings available

Page weight 2.1 MB over 1MB target

Got: 3.1 MB Expected: ≤ 1 MB

~146 KB of savings available

307 third-party resources (100% of weight)

2 resources over 200KB

308 resources · 3.1 MiB · 307 third-party 2.1 MiB over 1MB target

Image 67% · 2.1 MiB

JavaScript 22% · 688.1 KiB

Document 7% · 221.3 KiB

CSS 2% · 75.5 KiB

Font 1% · 38.5 KiB

Other 0% · 3.9 KiB

~145.7 KiB of savings available

Remove unused JavaScript: 145.7 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

308 resources			3.1 MiB

HTTP Caching

Action

No cache headers

FIX

No cache headers

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.

Image Optimization

86 images, 0 KB saveable

REVIEW

86 images, 0 KB saveable

All images are well-optimized

86 images 2.1 MB

0 oversized -0 KB

25 legacy format

0 missing dimensions CLS risk

JS Bundles

148 scripts, 146 KB unused

REVIEW

148 scripts, 146 KB unused

https://www.radiofrance.fr/_app/immutable/chunks/C...: 48 KB unused (66%)