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.
5.44 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
8.25 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.11 s
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.
5.44 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.
13.78 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction7373ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.zeit.de/index | 2879ms | 175ms | 24ms | 3rd |
| Unattributable | 973ms | 92ms | 0ms | 3rd |
| https://consent-cdn.zeit.de/Notice.8f529.js | 815ms | 569ms | 46ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MH96D5 | 538ms | 448ms | 81ms | 3rd |
| https://code.piano.io/api/tinypass.min.js | 375ms | 277ms | 60ms | 3rd |
| https://cdn.storifyme.xyz/static/web-components/storifyme-elements-v2.min.js | 310ms | 180ms | 19ms | 3rd |
| https://consent-cdn.zeit.de/wrapperMessagingWithoutDetection.js | 305ms | 196ms | 30ms | 3rd |
| https://interactive.zeit.de/g/wiegehtesihnen/app.5b89d5abbb910dab2c6e.cached.js | 249ms | 190ms | 19ms | 3rd |
| https://static.zeit.de/iqd/cdn_iqdzeit_mob/live/iqadcontroller.js | 219ms | 112ms | 100ms | 3rd |
| https://cdn.cxense.com/cx.js | 215ms | 122ms | 15ms | 3rd |
Showing top 10 of 14 scripts
DJS BundlesAction67 scripts, 320 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://code.piano.io/api/tinypass.min.js | 132 KB | 82 KB (63%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MH96D5 | 180 KB | 71 KB (40%) | ✓ | 3rd |
| https://consent-cdn.zeit.de/Notice.8f529.js | 91 KB | 63 KB (69%) | ✓ | 3rd |
| https://sp.zon.zeit.de/4.6.6/rl9os54c.js | 80 KB | 39 KB (49%) | ✓ | 3rd |
| https://consent-cdn.zeit.de/wrapperMessagingWithoutDetection.js | 51 KB | 22 KB (43%) | ✓ | 3rd |
| https://cdn.cxense.com/cx.js | 38 KB | 21 KB (57%) | ✓ | 3rd |
| https://cdn.cxense.com/cx.js | 38 KB | 21 KB (57%) | ✓ | 3rd |
| https://static.zeit.de/p/zeit.web/js/2638.54757e17384f0478.js | 1 KB | — | ✓ | 3rd |
| https://www.zeit.de/-/merkl/pages/_app/immutable/nodes/2.YoAKk0lX.js | 1 KB | — | ✓ | 3rd |
| https://interactive.zeit.de/g/2024/energiekostenmonitor/static/assets/preload-helper.95bd70cb.mjs | 1 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
DPage Weight InventoryAction127 resources · 2.0 MB · 320 KB savings availableFIX
~319.8 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 127 resources | 2.0 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CPage Weight BudgetAction2.0 MB transferred, 127 requestsREVIEW
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
BImage Optimization7 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.
Performance issues directly impact user engagement and conversion rates.
A+Text CompressionAll text resources are compressedPASS
A+Font Loading7 fonts (191 KB)PASS
Web fonts
7
191 KB total
Render-blocking
0
of 7
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
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)
Fixing the unchecked items could save ~10 KB and ~20 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints5 hints, 0 missing preconnectsPASS
Current Resource Hints
5 resource hints configured
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 Waterfall127 requests over 3341msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.zeit.de www.zeit.de | Other | 2879ms | 328 KB | — | €31/mo | Costly |
Unattributable Unattributable | Other | 973ms | 0 KB | — | €11/mo | Costly |
consent-cdn.zeit.de consent-cdn.zeit.de | Other | 815ms | 91 KB | 69% | €9/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 538ms | 180 KB | 40% | €6/mo | Costly |
code.piano.io code.piano.io | Other | 375ms | 132 KB | 63% | €4/mo | Costly |
cdn.storifyme.xyz cdn.storifyme.xyz | Other | 310ms | 32 KB | — | €3/mo | Costly |
consent-cdn.zeit.de consent-cdn.zeit.de | Other | 305ms | 51 KB | 43% | €3/mo | Costly |
interactive.zeit.de interactive.zeit.de | Other | 249ms | 45 KB | — | €3/mo | Costly |
static.zeit.de static.zeit.de | Other | 219ms | 68 KB | — | €2/mo | Costly |
cdn.cxense.com cdn.cxense.com | Other | 215ms | 38 KB | 57% | €2/mo | Costly |
sp.zon.zeit.de sp.zon.zeit.de | Other | 169ms | 80 KB | 49% | €2/mo | Optional |
static.zeit.de static.zeit.de | Other | 132ms | 10 KB | — | €1/mo | Optional |
www.zeit.de www.zeit.de | Other | 101ms | 22 KB | — | €1/mo | Optional |
consent-cdn.zeit.de consent-cdn.zeit.de | Other | 92ms | 2 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.zeit.de adds 2879ms and costs ~€31/month
- Unattributable adds 973ms and costs ~€11/month
- consent-cdn.zeit.de adds 815ms and costs ~€9/month
- Google Tag Manager adds 538ms and costs ~€6/month
- code.piano.io adds 375ms and costs ~€4/month
- cdn.storifyme.xyz adds 310ms and costs ~€3/month
- consent-cdn.zeit.de adds 305ms and costs ~€3/month
- interactive.zeit.de adds 249ms and costs ~€3/month
- static.zeit.de adds 219ms and costs ~€2/month
- cdn.cxense.com adds 215ms and costs ~€2/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.zeit.de takes 2879ms 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
Unattributable takes 973ms 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
consent-cdn.zeit.de takes 815ms 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
69% of consent-cdn.zeit.de'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
Google Tag Manager takes 538ms 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
code.piano.io takes 375ms 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
63% of code.piano.io'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
cdn.storifyme.xyz takes 310ms 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
consent-cdn.zeit.de takes 305ms 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
interactive.zeit.de takes 249ms 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
static.zeit.de takes 219ms 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
cdn.cxense.com takes 215ms 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
57% of cdn.cxense.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