Performance

· 16 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

100

Accessibility

100

Best Practices

SEO

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

2.34 s

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

3.33 s

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

78 ms

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

0.002

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

2.34 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.

4.46 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

9 PASS 2 REVIEW 3 FIX

Page Weight Budget

Action

2.2 MB transferred, 82 requests

FIX

2.2 MB transferred, 82 requests

Page weighs 3.9 MB (2.2 MB transferred)

82 HTTP requests

Estimated 0.47 g CO2 per page load

2.2 MB transferred

82 requests

0.47 g CO2 per page load

Other 1.2 MiB 53%

Other 650.5 KiB 28%

Fonts 199.4 KiB 9%

JavaScript 119.7 KiB 5%

Images 69.0 KiB 3%

HTML 17.9 KiB 1%

CSS 16.9 KiB 1%

Other 2.0 KiB 0%

Other 401 B 0%

0 2.4 MB 4.9 MB

Approaching limit

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 (2.2 MiB of 2.2 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

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.

JS Execution Cost

Action

1753ms total JS execution

REVIEW

1753ms total JS execution

https://mullvad.net/en: 866ms CPU time

Unattributable: 557ms CPU time

https://mullvad.net/_app/immutable/chunks/CbqrmVTX...: 330ms CPU time

Third-party scripts: 1753ms (100% of total)

Main Thread Breakdown

Other 34% Style & Layout 33% Script Evaluation 23% Rendering 6%

Script	Total	Scripting	Parse/Compile	Party
https://mullvad.net/en	866ms	14ms	6ms	3rd
Unattributable	557ms	131ms	0ms	3rd
https://mullvad.net/_app/immutable/chunks/CbqrmVTX.js	330ms	285ms	1ms	3rd

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

A+

Text Compression

All text resources are compressed

PASS

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

https://media.mullvad.net/web/desktop-2024.png?wid... is missing width/height — may cause layout shift

Set explicit width and height to prevent CLS.

3 images 69 KB

0 oversized -0 KB

0 legacy format

1 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

A+

Font Loading

13 fonts (199 KB)

PASS

13 fonts (199 KB)

13 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

199 KB total

Render-blocking

of 13

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

martian-mono-latin-wght... woff2 swap

Size 23 KB

Load time 0 ms

Start 0 ms