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.
465 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.39 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 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.
806 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.
2.45 s
Page Load Progression
397 ms
795 ms
1.2 s
1.6 s 2.0 s 2.4 s 2.8 s
3.2 sFPage Weight BudgetAction3.9 MB transferred, 80 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
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
CImage OptimizationAction68 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
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
BJS Execution Cost505ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| Unattributable | 271ms | 5ms | 0ms | 3rd |
| https://xonbet.net/ | 180ms | 1ms | 0ms | 1st |
| https://xonbet.net/build/frontend/app.js | 55ms | 30ms | 3ms | 1st |
CPage Weight InventoryAction80 resources · 3.9 MB · 0 KB savings availableREVIEW
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 80 resources | 3.9 MiB | ||||||
BHTTP Cachingno-cache, privateREVIEW
no-cache, private
| Directive | Value | Meaning |
|---|---|---|
| no-cache | — | Cache but always revalidate first |
| private | — | Only browser cache, not CDN/proxy |
A+Third-Party Impact0% third-party, 0 ms blockingPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading3 fonts (412 KB)PASS
Web fonts
3
412 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~330 KB and ~660 ms
AJS Bundles4 scripts, 0 KB unusedPASS
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://xonbet.net/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js | 1 KB | — | ✓ | 1st |
| https://xonbet.net/build/frontend/runtime.js | 5 KB | — | ✗ | 1st |
| https://xonbet.net/build/frontend/app.js | 28 KB | — | ✓ | 1st |
| https://static.cloudflareinsights.com/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da1771523124516 | 11 KB | — | ✓ | 3rd |
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: Cloudflare
Network Waterfall80 requests over 866msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 271ms | 0 KB | — | zł7/mo | Costly |
These scripts may cost more than they're worth
- Unattributable adds 271ms and costs ~zł7/month
54% of JavaScript execution time comes from third-party scripts.
Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.
Learn more ▾ ▴
Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.
Source: web.dev / HTTP Archive Web Almanac
Unattributable takes 271ms 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