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.

1.30 s

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

2.76 s

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

90 ms

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

0.009

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

2.68 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.

3.77 s

Page Load Progression

559 ms

1.1 s

1.7 s

2.2 s

2.8 s

3.4 s

3.9 s

4.5 s

Checks

5 PASS 3 REVIEW 5 FIX

Page Weight Budget

Action

3.1 MB transferred, 221 requests

FIX

3.1 MB transferred, 221 requests

Page weighs 10.0 MB (3.1 MB transferred)

JavaScript is 1.9 MB — consider code splitting or lazy loading

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

Got: 1.9 MB

CSS is 312 KB — consider purging unused styles

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Got: 312 KB

221 HTTP requests — consider bundling or reducing

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

Estimated 0.64 g CO2 per page load

3.1 MB transferred

221 requests

0.64 g CO2 per page load

JavaScript 1.9 MiB 62%

Other 384.5 KiB 12%

Images 356.8 KiB 11%

CSS 311.7 KiB 10%

HTML 100.1 KiB 3%

Other 23.3 KiB 1%

Other 2.0 KiB 0%

Other 1.5 KiB 0%

Other 643 B 0%

Other 314 B 0%

Fonts 0 B 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

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Why this matters

CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.

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

2934ms total JS execution

FIX

2934ms total JS execution

https://www.airbnb.com/: 718ms CPU time

Unattributable: 477ms CPU time

https://a0.muscache.com/airbnb/static/packages/web...: 445ms CPU time

https://a0.muscache.com/airbnb/static/packages/web...: 376ms CPU time

https://www.googletagmanager.com/gtm.js?id=GTM-46M...: 151ms CPU time

Third-party scripts: 2934ms (100% of total)

Main Thread Breakdown

Script Evaluation 60% Other 21% Style & Layout 7% Script Parsing & Compilation 5%

Script	Total	Scripting	Parse/Compile	Party
https://www.airbnb.com/	718ms	450ms	1ms	3rd
Unattributable	477ms	32ms	0ms	3rd
https://a0.muscache.com/airbnb/static/packages/web/en/e77e.33160b3545.js	445ms	362ms	2ms	3rd
https://a0.muscache.com/airbnb/static/packages/web/common/2ce9.b07975b17d.js	376ms	234ms	3ms	3rd
https://www.googletagmanager.com/gtm.js?id=GTM-46MK	151ms	137ms	12ms	3rd
https://a0.muscache.com/airbnb/static/packages/web/common/0a77.96fdfdbf95.js	150ms	17ms	3ms	3rd
https://a0.muscache.com/airbnb/static/packages/web/en/frontend/homepage/routes/TabbedVerticalHomepageRoute/TabbedVerticalHomepageRoute.1bd27b9ca4.js	110ms	80ms	4ms	3rd
https://www.googletagmanager.com/gtag/js?id=G-2P6Q8PGG16&cx=c&gtm=4e64f0	102ms	86ms	13ms	3rd
https://a0.muscache.com/airbnb/static/packages/web/en/frontend/core-guest-loop/apps/core-guest-spa/client.fdb4f57252.js	93ms	83ms	7ms	3rd
https://d0a7e.airbnb.com/tags.js	91ms	70ms	2ms	3rd

Showing top 10 of 13 scripts

Page Weight Inventory

Action

221 resources · 3.1 MB · 281 KB savings available

FIX

221 resources · 3.1 MB · 281 KB savings available

Page weight 2.1 MB over 1MB target

Got: 3.1 MB Expected: ≤ 1 MB

~281 KB of savings available

220 third-party resources (100% of weight)

1 resources over 200KB

221 resources · 3.1 MiB · 220 third-party 2.1 MiB over 1MB target

JavaScript 62% · 1.9 MiB

Media 12% · 384.5 KiB

Image 11% · 358.3 KiB

CSS 10% · 311.7 KiB

Document 3% · 100.7 KiB

Other 1% · 25.7 KiB

Font 0% · 0 B

~280.9 KiB of savings available

Remove unused JavaScript: 280.9 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

221 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

71 images, 0 KB saveable

REVIEW

71 images, 0 KB saveable

All images are well-optimized

71 images 357 KB

0 oversized -0 KB

12 legacy format

0 missing dimensions CLS risk

JS Bundles

Action

83 scripts, 281 KB unused

REVIEW

83 scripts, 281 KB unused

https://www.googletagmanager.com/gtag/js?id=G-2P6Q...: 63 KB unused (39%)