Performance
· 15 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.
910 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.09 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
611 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.003
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
5.98 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.
3.64 s
Page Load Progression
FPage Weight BudgetAction9.2 MB transferred, 54 requestsFIX
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
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
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction3982ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.komoot.com/assets/main.21fbfe92675e4f80.js | 1743ms | 1234ms | 48ms | 3rd |
| https://www.komoot.com/ | 884ms | 38ms | 224ms | 3rd |
| https://www.komoot.com/assets/23755.a9c34da1a4836155.js | 826ms | 819ms | 6ms | 3rd |
| Unattributable | 280ms | 5ms | 0ms | 3rd |
| https://www.komoot.com/assets/63200.9cf71bda3084be03.js | 172ms | 123ms | 48ms | 3rd |
| https://www.komoot.com/assets/13477.d9051ea950027b93.js | 78ms | 46ms | 31ms | 3rd |
DJS BundlesAction19 scripts, 369 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.komoot.com/assets/main.21fbfe92675e4f80.js | 564 KB | 241 KB (43%) | ✓ | 3rd |
| https://www.komoot.com/assets/38339.5c593cadcec7993e.js | 99 KB | 84 KB (85%) | ✓ | 3rd |
| https://www.komoot.com/assets/23755.a9c34da1a4836155.js | 75 KB | 44 KB (58%) | ✓ | 3rd |
| https://www.komoot.com/assets/17429.d6019cb8292fe181.js | 13 KB | — | ✓ | 3rd |
| https://www.komoot.com/assets/39350.422b33588c622344.js | 5 KB | — | ✓ | 3rd |
| https://www.komoot.com/assets/56408.9b1d3f09f8e85b10.js | 6 KB | — | ✓ | 3rd |
| https://www.komoot.com/assets/3343.75dd63c212f21b99.js | 6 KB | — | ✓ | 3rd |
| https://www.komoot.com/assets/34414.344fc393842ba469.js | 5 KB | — | ✓ | 3rd |
| https://www.komoot.com/assets/12904.e913e7e6ef3838de.js | 1 KB | — | ✓ | 3rd |
| https://www.komoot.com/assets/63200.9cf71bda3084be03.js | 54 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
DPage Weight InventoryAction54 resources · 9.2 MB · 369 KB savings availableFIX
~369.5 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 54 resources | 9.2 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization20 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
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
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading6 fonts (91 KB)PASS
Web fonts
6
91 KB total
Render-blocking
0
of 6
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
Network Waterfall54 requests over 8047msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.komoot.com www.komoot.com | Other | 1743ms | 564 KB | 43% | €19/mo | Costly |
www.komoot.com www.komoot.com | Other | 884ms | 433 KB | — | €10/mo | Costly |
www.komoot.com www.komoot.com | Other | 826ms | 75 KB | 58% | €9/mo | Costly |
Unattributable Unattributable | Other | 280ms | 0 KB | — | €3/mo | Costly |
www.komoot.com www.komoot.com | Other | 172ms | 54 KB | — | €2/mo | Optional |
www.komoot.com www.komoot.com | Other | 78ms | 234 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.komoot.com adds 1743ms and costs ~€19/month
- www.komoot.com adds 884ms and costs ~€10/month
- www.komoot.com adds 826ms and costs ~€9/month
- Unattributable adds 280ms and costs ~€3/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
www.komoot.com takes 1743ms 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.komoot.com takes 884ms 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.komoot.com takes 826ms 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
58% of www.komoot.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
Unattributable takes 280ms 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