Performance
· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
5.02 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
22.48 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
579 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.
13.56 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.
24.54 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 sFPage Weight BudgetAction7.3 MB transferred, 275 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
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.
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.
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction5414ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| Unattributable | 1496ms | 189ms | 0ms | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_chunk-2d21061a.04852039.js | 1249ms | 1165ms | 0ms | 3rd |
| https://www.justwatch.com/ | 1161ms | 34ms | 152ms | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_app.d118834e.js | 524ms | 427ms | 83ms | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_npm.sentry.7ab7f5b8.js | 276ms | 231ms | 16ms | 3rd |
| https://accounts.justwatch.com/__/auth/iframe.js | 141ms | 108ms | 24ms | 3rd |
| https://web.cmp.usercentrics.eu/ui/v/3.117.0/WebSdk.lib.4c6726a9.js | 139ms | 104ms | 27ms | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_npm.sentry-internal.e50f9ed8.js | 132ms | 114ms | 14ms | 3rd |
| https://web.cmp.usercentrics.eu/ui/v/3.117.0/UcTcfCmpView.d21ff1d8.js | 106ms | 47ms | 11ms | 3rd |
| https://apis.google.com/_/scs/abc-static/_/js/k=gapi.lb.en.PJsh2cctCQI.O/m=gapi_iframes/rt=j/sv=1/d=1/ed=1/rs=AHpOoo_QlMhY2cycn60Rs8eI1WInRwuahw/cb=gapi.loaded_0?le=scs | 77ms | 65ms | 10ms | 3rd |
Showing top 10 of 12 scripts
DPage Weight InventoryAction275 resources · 7.3 MB · 269 KB savings availableFIX
~269.1 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 275 resources | 7.3 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction206 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
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.
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.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
CJS BundlesAction37 scripts, 269 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.justwatch.com/appassets/js/1776857142622_app.d118834e.js | 206 KB | 78 KB (38%) | ✓ | 3rd |
| https://accounts.justwatch.com/__/auth/iframe.js | 90 KB | 55 KB (61%) | ✓ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_npm.sentry-internal.e50f9ed8.js | 52 KB | 43 KB (83%) | ✓ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_npm.sentry.7ab7f5b8.js | 58 KB | 41 KB (70%) | ✓ | 3rd |
| https://web.cmp.usercentrics.eu/ui/v/3.117.0/WebSdk.lib.4c6726a9.js | 56 KB | 30 KB (54%) | ✓ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_npm.firebase.05d26338.js | 41 KB | 22 KB (55%) | ✗ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_npm.graphql.0fdb0149.js | 10 KB | — | ✓ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_freemium-filter-badge.8181dbf3.js | 1 KB | — | ✓ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_low-priority-components.dc563ad3.js | 3 KB | — | ✓ | 3rd |
| https://www.justwatch.com/appassets/js/1776857142622_runtime.f4b651e0.js | 5 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
A+Text CompressionAll text resources are compressedPASS
A+Font Loading4 fonts (112 KB)PASS
Web fonts
4
112 KB total
Render-blocking
0
of 4
Dominant font-display
swap
Most common across fonts
Font loading timeline
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+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Google Cloud
Network Waterfall275 requests over 1852msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 1496ms | 0 KB | — | $20/mo | Costly |
www.justwatch.com www.justwatch.com | Other | 1249ms | 1 KB | — | $17/mo | Costly |
www.justwatch.com www.justwatch.com | Other | 1161ms | 187 KB | — | $15/mo | Costly |
www.justwatch.com www.justwatch.com | Other | 524ms | 206 KB | 38% | $7/mo | Costly |
www.justwatch.com www.justwatch.com | Other | 276ms | 58 KB | 70% | $4/mo | Costly |
accounts.justwatch.com accounts.justwatch.com | Other | 141ms | 90 KB | 61% | $2/mo | Optional |
web.cmp.usercentrics.eu web.cmp.usercentrics.eu | Other | 139ms | 56 KB | 54% | $2/mo | Optional |
www.justwatch.com www.justwatch.com | Other | 132ms | 52 KB | 83% | $2/mo | Optional |
web.cmp.usercentrics.eu web.cmp.usercentrics.eu | Other | 106ms | 22 KB | — | $1/mo | Optional |
apis.google.com apis.google.com | Other | 77ms | 34 KB | — | $1/mo | Optional |
web.cmp.usercentrics.eu web.cmp.usercentrics.eu | Other | 58ms | 1 KB | — | $1/mo | Optional |
web.cmp.usercentrics.eu web.cmp.usercentrics.eu | Other | 55ms | 12 KB | — | $1/mo | Optional |
These scripts may cost more than they're worth
- Unattributable adds 1496ms and costs ~$20/month
- www.justwatch.com adds 1249ms and costs ~$17/month
- www.justwatch.com adds 1161ms and costs ~$15/month
- www.justwatch.com adds 524ms and costs ~$7/month
- www.justwatch.com adds 276ms and costs ~$4/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
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
Unattributable takes 1496ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.justwatch.com takes 1249ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.justwatch.com takes 1161ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.justwatch.com takes 524ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.justwatch.com takes 276ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
70% of www.justwatch.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
61% of accounts.justwatch.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
54% of web.cmp.usercentrics.eu's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
83% of www.justwatch.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev