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

SEO

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

1.34 s

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

0 ms

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

0 ms

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

0.000

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

2.08 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.

0 ms

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

7 PASS 3 REVIEW 3 FIX

Page Weight Budget

Action

2.5 MB transferred, 204 requests

FIX

2.5 MB transferred, 204 requests

Page weighs 6.5 MB (2.5 MB transferred)

Images are 1.3 MB — compress or use modern formats

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

Got: 1.3 MB

JavaScript is 958 KB — consider code splitting or lazy loading

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

Got: 958 KB

204 HTTP requests — consider bundling or reducing

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

Estimated 0.53 g CO2 per page load

2.5 MB transferred

204 requests

0.53 g CO2 per page load

Images 1.3 MiB 52%

JavaScript 958.4 KiB 37%

HTML 114.6 KiB 4%

Fonts 94.8 KiB 4%

CSS 42.3 KiB 2%

Other 9.9 KiB 0%

Other 1.5 KiB 0%

Other 0 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 (2.5 MiB of 2.5 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

Page Weight Inventory

Action

204 resources · 2.5 MB · 0 KB savings available

FIX

204 resources · 2.5 MB · 0 KB savings available

Page weight 1.5 MB over 1MB target

Got: 2.5 MB Expected: ≤ 1 MB

197 third-party resources (100% of weight)

204 resources · 2.5 MiB · 197 third-party 1.5 MiB over 1MB target

Image 52% · 1.3 MiB

JavaScript 37% · 958.4 KiB

Document 5% · 115.8 KiB

Font 4% · 94.8 KiB

CSS 2% · 42.3 KiB

Other 0% · 9.9 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

204 resources			2.5 MiB

JS Execution Cost

Action

1945ms total JS execution

REVIEW

1945ms total JS execution

https://watch.plex.tv/_next/static/chunks/0b5~.n6c...: 1084ms CPU time

https://watch.plex.tv/: 506ms CPU time

Unattributable: 250ms CPU time

https://watch.plex.tv/_next/static/chunks/0-mdppug...: 104ms CPU time

Third-party scripts: 1945ms (100% of total)

Main Thread Breakdown

Script Evaluation 39% Other 34% Style & Layout 12% Rendering 5% Script Parsing & Compilation 5%

Script	Total	Scripting	Parse/Compile	Party
https://watch.plex.tv/_next/static/chunks/0b5~.n6cv._dk.js	1084ms	720ms	5ms	3rd
https://watch.plex.tv/	506ms	22ms	28ms	3rd
Unattributable	250ms	6ms	0ms	3rd
https://watch.plex.tv/_next/static/chunks/0-mdppugogl1w.js	104ms	1ms	2ms	3rd

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

HTTP Caching

no-cache

REVIEW

no-cache

Cache-Control header is set

Got: no-cache

No ETag or Last-Modified header

Conditional requests (304 Not Modified) are not possible without validators.

Cache-Control

no-cache

Directive	Value	Meaning
no-cache	—	Cache but always revalidate first

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Image Optimization

110 images, 0 KB saveable

PASS

110 images, 0 KB saveable

All images are well-optimized

110 images 1.3 MB

0 oversized -0 KB

0 legacy format

0 missing dimensions CLS risk

A+

Font Loading

2 fonts (95 KB)

PASS

2 fonts (95 KB)

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

Web fonts

95 KB total

Render-blocking

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

83afe278b6a6bb3c-s.p.0q... woff2 swap

Size 47 KB

Load time 32 ms

Start 646 ms

Risk FOUT — text flashes from fallback to web font

plexcircular_bold-s.p.0... woff2 swap

Size 47 KB

Load time 36 ms

Start 646 ms

Risk FOUT — text flashes from fallback to web font

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+

JS Bundles

41 scripts, 0 KB unused

PASS

41 scripts, 0 KB unused

0 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://js.sentry-cdn.com/eb76eae607a34d13b8a50419d1ffaee2.min.js	3 KB	—	✓	3rd
https://www.gstatic.com/cv/js/sender/v1/cast_sender.js?loadCastFramework=1	2 KB	—	✓	3rd
https://accounts.google.com/gsi/client	96 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/0nax_7a.ceb.t.js	8 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/0t6banju9ym1n.js	11 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/0e5~2qdnp-24t.js	38 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/0b5~.n6cv._dk.js	69 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/turbopack-0xkc.mlcbl-k3.js	4 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/04~las1adg2-2.js	3 KB	—	✓	3rd
https://watch.plex.tv/_next/static/chunks/0e9.97yalk.l6.js	13 KB	—	✓	3rd

A+

Resource Caching

All resources properly cached

PASS

All resources properly cached

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

A+

Resource Hints

No optimization needed

PASS

No optimization needed

No resource hint issues

Network Waterfall

204 requests over 2521ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

100% of JavaScript execution is third-party

First-party Third-party 1945ms · 198KB · CHF31/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
watch.plex.tv watch.plex.tv	Other	1084ms	69 KB	—	CHF17/mo	Costly
watch.plex.tv watch.plex.tv	Other	506ms	115 KB	—	CHF8/mo	Costly
Unattributable Unattributable	Other	250ms	0 KB	—	CHF4/mo	Costly
watch.plex.tv watch.plex.tv	Other	104ms	14 KB	—	CHF2/mo	Optional

watch.plex.tv

Other

Costly

Execution 1084ms

Transfer 69 KB

Monthly Cost CHF17/mo

watch.plex.tv

Other

Costly

Execution 506ms

Transfer 115 KB

Monthly Cost CHF8/mo

Unattributable

Other

Costly

Execution 250ms

Transfer 0 KB

Monthly Cost CHF4/mo

watch.plex.tv

Other

Optional

Execution 104ms

Transfer 14 KB

Monthly Cost CHF2/mo

These scripts may cost more than they're worth

watch.plex.tv adds 1084ms and costs ~CHF17/month
watch.plex.tv adds 506ms and costs ~CHF8/month
Unattributable adds 250ms and costs ~CHF4/month

100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

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

watch.plex.tv takes 1084ms 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

watch.plex.tv takes 506ms 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 250ms 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

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.