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https://www.doctolib.fr

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
75
GRADE
C
FIX
3
REVIEW
2
PASS
9
INFO
2

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

Mobile Desktop
27
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.
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.

6.60 s

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

8.20 s

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

4.07 s

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

0.096

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

6.62 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.

29.22 s

Page Load Progression

400 ms
799 ms
1.2 s
1.6 s
2.0 s
2.4 s
2.8 s
3.2 s
Checks
16
9 PASS 2 REVIEW 3 FIX
F
Page Weight Budget
Action
4.5 MB transferred, 84 requests
FIX
4.5 MB transferred, 84 requests
Critical::
Page weighs 18.5 MB (4.5 MB transferred)
Warning::
JavaScript is 3.6 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 3.6 MB
Info::
84 HTTP requests
Info::
Estimated 0.95 g CO2 per page load
4.5 MB / 2.4 MB budget
4.5 MB transferred
84 requests
0.95 g CO2 per page load
JavaScript 3.6 MiB 79%
HTML 533.4 KiB 11%
Images 173.2 KiB 4%
Fonts 159.7 KiB 3%
CSS 112.7 KiB 2%
Other 8.6 KiB 0%
Other 3.1 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

F
JS Execution Cost
Action
7898ms total JS execution
FIX
7898ms total JS execution
Warning::
https://www.doctolib.fr/rspack/js/7065-5ffe0f6af48...: 2435ms CPU time
Warning::
https://www.doctolib.fr/: 1311ms CPU time
Warning::
https://assets.doctolib.fr/static_webpack/rum-data...: 1233ms CPU time
Warning::
https://www.doctolib.fr/rspack/js/1882-6765ecea4d0...: 1001ms CPU time
Warning::
Unattributable: 664ms CPU time
Info::
Third-party scripts: 2509ms (32% of total)

Main Thread Breakdown

Script Evaluation 51% Script Parsing & Compilation 28% Other 9% Style & Layout 5% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://www.doctolib.fr/rspack/js/7065-5ffe0f6af487e235.chunk.js2435ms1476ms886ms1st
https://www.doctolib.fr/1311ms168ms353ms1st
https://assets.doctolib.fr/static_webpack/rum-datadog-c577014dd3dffb96a37d.js1233ms1065ms17ms3rd
https://www.doctolib.fr/rspack/js/1882-6765ecea4d0a05f7.chunk.js1001ms749ms250ms1st
Unattributable664ms81ms0ms3rd
https://www.doctolib.fr/rspack/js/7507-31dd49bd6aff766d.chunk.js304ms4ms300ms1st
https://www.doctolib.fr/rspack/js/552-2db91f5451ab3671.chunk.js276ms218ms57ms1st
https://sdk.privacy-center.org/sdk/c8e2e67c354c0d6dec2981e079061b37f6a1f337/modern/ui-web-en-web.c8e2e67c354c0d6dec2981e079061b37f6a1f337.js199ms100ms34ms3rd
https://sdk.privacy-center.org/sdk/c8e2e67c354c0d6dec2981e079061b37f6a1f337/modern/sdk.c8e2e67c354c0d6dec2981e079061b37f6a1f337.js197ms155ms42ms3rd
https://assets.doctolib.fr/static_webpack/sentry-7ca06c94a727794a.js144ms89ms55ms3rd

Showing top 10 of 12 scripts

F
JS Bundles
Action
52 scripts, 2.0 MB unused
FIX
52 scripts, 2.0 MB unused
Warning::
https://www.doctolib.fr/rspack/js/7065-5ffe0f6af48...: 845 KB unused (58%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.doctolib.fr/rspack/js/1882-6765ecea4d0...: 374 KB unused (69%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.doctolib.fr/rspack/js/7507-31dd49bd6af...: 295 KB unused (55%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://assets.doctolib.fr/static_webpack/sentry-7...: 107 KB unused (80%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.doctolib.fr/rspack/js/3124-b1bcc4c2848...: 95 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 2.0 MB
2017 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.doctolib.fr/rspack/js/7065-5ffe0f6af487e235.chunk.js1460 KB845 KB (58%)✓1st
https://www.doctolib.fr/rspack/js/1882-6765ecea4d0a05f7.chunk.js542 KB374 KB (69%)✓1st
https://www.doctolib.fr/rspack/js/7507-31dd49bd6aff766d.chunk.js536 KB295 KB (55%)✓1st
https://assets.doctolib.fr/static_webpack/sentry-7ca06c94a727794a.js133 KB107 KB (80%)✓3rd
https://www.doctolib.fr/rspack/js/3124-b1bcc4c284825921.chunk.js179 KB95 KB (53%)✓1st
https://assets.doctolib.fr/rspack/9270-2f06da1927c78bba.js123 KB61 KB (50%)✓3rd
https://www.doctolib.fr/rspack/js/552-2db91f5451ab3671.chunk.js65 KB53 KB (82%)✓1st
https://www.datadoghq-browser-agent.com/datadog-rum-v4.js48 KB45 KB (94%)✓3rd
https://sdk.privacy-center.org/sdk/c8e2e67c354c0d6dec2981e079061b37f6a1f337/modern/sdk.c8e2e67c354c0d6dec2981e079061b37f6a1f337.js91 KB44 KB (49%)✓3rd
https://www.doctolib.fr/rspack/js/3382-7382d16ec06f7638.chunk.js36 KB32 KB (89%)✓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

C
Image Optimization
Action
14 images, 0 KB saveable
REVIEW
14 images, 0 KB saveable
Warning::
https://www.doctolib.fr/rspack/6fb057589f3aefde.sv... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/6da930dd4a069e39.sv... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/89445a7a32b87f02.pn... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/4fbe366ca9e68fb1.we... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/664d75bfddbc37ec.we... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/faa21d0cfa490633.we... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/8a95e5cdf4bbfee1.sv... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/8f81baac0935f0cd.pn... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/cccb491a7203bd7a.sv... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.doctolib.fr/rspack/ce38df5c086a2d71.we... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
14 images 173 KB
0 oversized -0 KB
10 legacy format
10 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

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
max-age=0, private, must-revalidate
REVIEW
max-age=0, private, must-revalidate
Info::
Cache-Control header is set
Got: max-age=0, private, must-revalidate
Info::
ETag present — enables conditional (304) responses
Cache-Control

max-age=0, private, must-revalidate

DirectiveValueMeaning
max-age0Cache for 0 seconds
private—Only browser cache, not CDN/proxy
must-revalidate—Must recheck with server after expiry
A+
Third-Party Impact
16% third-party, 0 ms blocking
PASS
16% third-party, 0 ms blocking
Info::
Third-party code accounts for 16% of page weight (738.8 KiB of 4.5 MiB)
Info::
Third-party blocking time is low (0 ms)
84%
16%
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 (160 KB)
PASS
4 fonts (160 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

160 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 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s 7.0 s 8.0 s FCP 6.6 s LCP 8.2 shttps://assets.doctolib.fr/fonts/font-roboto-regular.ttffont-roboto-regular.ttf https://assets.doctolib.fr/fonts/font-roboto-regular.ttf — 35.1 KiB — 0 ms — font-display: swaphttps://assets.doctolib.fr/fonts/font-roboto-bold.ttffont-roboto-bold.ttf https://assets.doctolib.fr/fonts/font-roboto-bold.ttf — 35.2 KiB — 0 ms — font-display: swaphttps://assets.doctolib.fr/fonts/font-montserrat-regular.ttffont-montserrat-regular... https://assets.doctolib.fr/fonts/font-montserrat-regular.ttf — 44.4 KiB — 0 ms — font-display: swaphttps://assets.doctolib.fr/fonts/font-montserrat-bold.ttffont-montserrat-bold.ttf https://assets.doctolib.fr/fonts/font-montserrat-bold.ttf — 45.1 KiB — 0 ms — font-display: swap
font-roboto-regular.ttf ttf 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
font-roboto-bold.ttf ttf 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
font-montserrat-regular... ttf swap
Size 44 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
font-montserrat-bold.ttf ttf swap
Size 45 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 ~48 KB and ~96 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
84 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
32% of JavaScript execution is third-party
First-party Third-party 2509ms · 453KB · €27/mo
assets.doctolib.fr
Other
Costly
Execution 1233ms
Transfer 52 KB
Unused 45%
Monthly Cost €13/mo
Unattributable
Other
Costly
Execution 664ms
Transfer 0 KB
Monthly Cost €7/mo
sdk.privacy-center.org
Other
Optional
Execution 199ms
Transfer 54 KB
Monthly Cost €2/mo
sdk.privacy-center.org
Other
Optional
Execution 197ms
Transfer 91 KB
Unused 49%
Monthly Cost €2/mo
assets.doctolib.fr
Other
Optional
Execution 144ms
Transfer 133 KB
Unused 80%
Monthly Cost €2/mo
assets.doctolib.fr
Other
Optional
Execution 71ms
Transfer 123 KB
Unused 50%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • assets.doctolib.fr adds 1233ms and costs ~€13/month
  • Unattributable adds 664ms and costs ~€7/month

assets.doctolib.fr takes 1233ms 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

Unattributable takes 664ms 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

80% of assets.doctolib.fr'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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