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.
855 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.00 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
96 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.
977 ms
Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.
3.09 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 BudgetAction6.0 MB transferred, 104 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 BundlesAction8 scripts, 612 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.deutschlandfunk.de/static/generated/deutschlandfunk/main.modern.js | 670 KB | 312 KB (47%) | ✓ | 3rd |
| https://www.deutschlandfunk.de/static/podlove-player/5.12.3/player/vendor.js | 237 KB | 146 KB (62%) | ✓ | 3rd |
| https://www.deutschlandfunk.de/static/generated/deutschlandfunk/player.dist.js | 160 KB | 121 KB (76%) | ✓ | 3rd |
| https://www.deutschlandfunk.de/static/podlove-player/5.12.3/player/styles.js | 45 KB | 33 KB (73%) | ✓ | 3rd |
| https://www.deutschlandfunk.de/static/podlove-player/embed.js | 43 KB | — | ✓ | 3rd |
| https://tag.aticdn.net/piano-analytics.js | 27 KB | — | ✓ | 3rd |
| https://www.deutschlandfunk.de/static/podlove-player/variant-xl.js | 1 KB | — | ✓ | 3rd |
| https://www.deutschlandfunk.de/static/podlove-player/5.12.3/player/bootstrap.js | 32 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
FPage Weight InventoryAction104 resources · 6.0 MB · 612 KB savings availableFIX
~611.7 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 104 resources | 6.0 MiB | ||||||
BImage Optimization84 images, 0 KB saveableREVIEW
BJS Execution Cost884ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.deutschlandfunk.de/static/generated/deutschlandfunk/main.modern.js | 295ms | 248ms | 3ms | 3rd |
| Unattributable | 183ms | 3ms | 0ms | 3rd |
| https://www.deutschlandfunk.de/ | 168ms | 10ms | 1ms | 3rd |
| https://www.deutschlandfunk.de/static/podlove-player/5.12.3/player/bootstrap.js | 134ms | 131ms | 3ms | 3rd |
| https://www.deutschlandfunk.de/static/generated/deutschlandfunk/player.dist.js | 103ms | 41ms | 15ms | 3rd |
BHTTP CachingprivateREVIEW
private
| Directive | Value | Meaning |
|---|---|---|
| private | — | Only browser cache, not CDN/proxy |
A+Text CompressionAll text resources are compressedPASS
A+Font Loading4 fonts (142 KB)PASS
Web fonts
4
142 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+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Google Cloud
Network Waterfall104 requests over 1153msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.deutschlandfunk.de www.deutschlandfunk.de | Other | 295ms | 670 KB | 47% | €3/mo | Costly |
Unattributable Unattributable | Other | 183ms | 0 KB | — | €2/mo | Optional |
www.deutschlandfunk.de www.deutschlandfunk.de | Other | 168ms | 299 KB | — | €2/mo | Optional |
www.deutschlandfunk.de www.deutschlandfunk.de | Other | 134ms | 32 KB | — | €1/mo | Optional |
www.deutschlandfunk.de www.deutschlandfunk.de | Other | 103ms | 160 KB | 76% | €1/mo | Optional |
These scripts may cost more than they're worth
- www.deutschlandfunk.de adds 295ms 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.deutschlandfunk.de takes 295ms 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
76% of www.deutschlandfunk.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