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.
4.77 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
18.56 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.14 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.005
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
8.40 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.
20.88 s
Page Load Progression
DPage Weight BudgetAction2.6 MB transferred, 194 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
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
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 CostAction5469ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| Unattributable | 900ms | 82ms | 0ms | 3rd |
| https://livebar.onet.pl/mobile/02a91f84-1fd4-4d29-98fc-8c4d78b258d7 | 628ms | 1ms | 2ms | 3rd |
| https://sgqcvfjvr.onet.pl/build/dlApi/dl.cmp.min.js?5&79c5d6bb3d969df9bbd25ac7433130b5 | 578ms | 501ms | 14ms | 3rd |
| https://static.onet.pl/_next/static/chunks/framework-d1ebf998e09197cf.js | 423ms | 398ms | 11ms | 3rd |
| https://www.onet.pl/ | 413ms | 106ms | 14ms | 3rd |
| https://cmp.dreamlab.pl/static-v2/cmp.bundle.js?v=225 | 400ms | 346ms | 14ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-P85SF2J | 323ms | 268ms | 52ms | 3rd |
| https://cdn-eu.piano.io/api/piano.js | 297ms | 219ms | 52ms | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604170101/pubads_impl.js?cb=31097963 | 211ms | 115ms | 46ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-3TN10DTZCJ&cx=c>m=4e64h1 | 205ms | 166ms | 38ms | 3rd |
Showing top 10 of 20 scripts
FJS BundlesAction99 scripts, 514 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604170101/pubads_impl.js?cb=31097963 | 187 KB | 141 KB (75%) | ✓ | 3rd |
| https://cdn-eu.piano.io/api/piano.js | 133 KB | 85 KB (64%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-P85SF2J | 156 KB | 75 KB (48%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-3TN10DTZCJ&cx=c>m=4e64h1 | 160 KB | 68 KB (43%) | ✓ | 3rd |
| https://sgqcvfjvr.onet.pl/YnVpbGQvezlza2x0NjYzfWRsQXBpL2RsLmxpYntOTWFzXzY2M30ubWluLmpz | 108 KB | 59 KB (55%) | ✓ | 3rd |
| https://cdn.raspaid.pl/script/paywall.slim.min.js?v=mo70ug7b | 60 KB | 42 KB (70%) | ✓ | 3rd |
| https://cdn.cxense.com/cx.js | 38 KB | 22 KB (58%) | ✓ | 3rd |
| https://cmp.dreamlab.pl/static-v2/cmp.bundle.js?v=225 | 53 KB | 22 KB (41%) | ✓ | 3rd |
| https://securepubads.g.doubleclick.net/tag/js/gpt.js?no_cache=1 | 34 KB | — | ✓ | 3rd |
| https://static.onet.pl/_next/static/chunks/pages/_app-ae88a00a4dc2171e.js | 46 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
FPage Weight InventoryAction194 resources · 2.6 MB · 514 KB savings availableFIX
~514.2 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 194 resources | 2.6 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization25 images, 0 KB saveableREVIEW
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 Loading8 fonts (242 KB)PASS
Web fonts
8
242 KB total
Render-blocking
0
of 8
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 Hints17 hints, 0 missing preconnectsPASS
Current Resource Hints
17 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall194 requests over 6221msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 900ms | 0 KB | — | zł22/mo | Costly |
livebar.onet.pl livebar.onet.pl | Other | 628ms | 3 KB | — | zł16/mo | Costly |
sgqcvfjvr.onet.pl sgqcvfjvr.onet.pl | Other | 578ms | 40 KB | — | zł14/mo | Costly |
static.onet.pl static.onet.pl | Other | 423ms | 42 KB | — | zł10/mo | Costly |
www.onet.pl www.onet.pl | Other | 413ms | 41 KB | — | zł10/mo | Costly |
cmp.dreamlab.pl cmp.dreamlab.pl | Other | 400ms | 53 KB | 41% | zł10/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 323ms | 156 KB | 48% | zł8/mo | Costly |
cdn-eu.piano.io cdn-eu.piano.io | Other | 297ms | 133 KB | 64% | zł7/mo | Costly |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 211ms | 187 KB | 75% | zł5/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 205ms | 160 KB | 43% | zł5/mo | Costly |
static.onet.pl static.onet.pl | Other | 175ms | 1 KB | — | zł4/mo | Optional |
www.npttech.com www.npttech.com | Other | 175ms | 3 KB | — | zł4/mo | Optional |
sgqcvfjvr.onet.pl sgqcvfjvr.onet.pl | Other | 166ms | 108 KB | 55% | zł4/mo | Optional |
static.onet.pl static.onet.pl | Other | 113ms | 46 KB | — | zł3/mo | Optional |
static.onet.pl static.onet.pl | Other | 102ms | 39 KB | — | zł3/mo | Optional |
cdn.raspaid.pl cdn.raspaid.pl | Other | 95ms | 60 KB | 70% | zł2/mo | Optional |
cdn.cxense.com cdn.cxense.com | Other | 91ms | 38 KB | 58% | zł2/mo | Optional |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 61ms | 34 KB | — | zł2/mo | Optional |
rasp.salesmanago.com rasp.salesmanago.com | Other | 58ms | 17 KB | — | zł1/mo | Optional |
s-eu-1.pushpushgo.com s-eu-1.pushpushgo.com | Other | 54ms | 4 KB | — | zł1/mo | Optional |
These scripts may cost more than they're worth
- Unattributable adds 900ms and costs ~zł22/month
- livebar.onet.pl adds 628ms and costs ~zł16/month
- sgqcvfjvr.onet.pl adds 578ms and costs ~zł14/month
- static.onet.pl adds 423ms and costs ~zł10/month
- www.onet.pl adds 413ms and costs ~zł10/month
- cmp.dreamlab.pl adds 400ms and costs ~zł10/month
- Google Tag Manager adds 323ms and costs ~zł8/month
- cdn-eu.piano.io adds 297ms and costs ~zł7/month
- securepubads.g.doubleclick.net adds 211ms and costs ~zł5/month
- Google Tag Manager adds 205ms and costs ~zł5/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 900ms 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
livebar.onet.pl takes 628ms 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
sgqcvfjvr.onet.pl takes 578ms 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.onet.pl takes 423ms 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.onet.pl takes 413ms 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
cmp.dreamlab.pl takes 400ms 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
Google Tag Manager takes 323ms 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-eu.piano.io takes 297ms 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
64% of cdn-eu.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
securepubads.g.doubleclick.net takes 211ms 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
75% of securepubads.g.doubleclick.net'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 205ms 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
55% of sgqcvfjvr.onet.pl'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
70% of cdn.raspaid.pl'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
58% 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