Performance
· 28 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.
9.82 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
34.59 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
5.09 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.
10.68 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.
34.95 s
Page Load Progression
FPage Weight BudgetAction6.7 MB transferred, 184 requestsFIX
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
FJS Execution CostAction11318ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://psichologie.cz/_framework/blazor.web.js | 6275ms | 5915ms | 18ms | 1st |
| Unattributable | 2000ms | 657ms | 0ms | 1st |
| https://psichologie.cz/_framework/dotnet.native.7dko1v9rxe.js | 1309ms | 1301ms | 1ms | 1st |
| https://psichologie.cz/ | 748ms | 15ms | 2ms | 1st |
| https://d70shl7vidtft.cloudfront.net/ecmtr-2.4.2.js | 580ms | 146ms | 8ms | 3rd |
| https://psichologie.cz/js/carousel.86ps4ni65l.js | 406ms | 311ms | 0ms | 1st |
DHTTP CachingActionno-store (uncacheable)FIX
no-cache, no-store
| Directive | Value | Meaning |
|---|---|---|
| no-cache | — | Cache but always revalidate first |
| no-store | — | Never cache this response |
CImage OptimizationAction65 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
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 Bundles12 scripts, 115 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://psichologie.cz/_framework/blazor.web.js | 55 KB | 41 KB (74%) | ✓ | 1st |
| https://psichologie.cz/_framework/dotnet.native.7dko1v9rxe.js | 62 KB | 38 KB (62%) | ✗ | 1st |
| https://psichologie.cz/_framework/dotnet.runtime.zbexyp8zrs.js | 55 KB | 36 KB (65%) | ✓ | 1st |
| https://psichologie.cz/lib/bootstrap/dist/js/bootstrap.bundle.min.t00mg49bzh.js | 21 KB | — | ✓ | 1st |
| https://psichologie.cz/js/site.blvc3njm1h.js | 1 KB | — | ✓ | 1st |
| https://psichologie.cz/js/cookie-consent.ioqaqduiy7.js | 2 KB | — | ✓ | 1st |
| https://d70shl7vidtft.cloudfront.net/ecmtr-2.4.2.js | 18 KB | — | ✓ | 3rd |
| https://psichologie.cz/_framework/dotnet.y9uzsa2o1o.js | 16 KB | — | ✓ | 1st |
| https://psichologie.cz/_framework/resource-collection.uVZjQ.js | 44 KB | — | ✓ | 1st |
| https://psichologie.cz/js/input.utgzzqkzyr.js | 1 KB | — | ✓ | 1st |
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
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
CPage Weight InventoryAction184 resources · 6.7 MB · 115 KB savings availableREVIEW
~114.5 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 184 resources | 6.7 MiB | ||||||
BJavaScript Blocking2 JS blocking issue(s) detectedREVIEW
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Third-Party Impact0% third-party, 0 ms blockingPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading6 fonts (959 KB)PASS
Web fonts
6
959 KB total
Render-blocking
0
of 6
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
- 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
- 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 ~716 KB and ~1432 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints3 hints, 0 missing preconnectsPASS
Current Resource Hints
3 resource hints configured
A+Document CompressionDocument response uses brotliPASS
A+Asset CompressionAll 1 asset host use brotliPASS
A+LCP Image PreloadLCP preload audit not availablePASS
A+Main HTML Cache-ControlMain HTML uses no-store -- correct for sensitive/dynamic contentPASS
A+Server Response Intelligence2 server-response signal(s) detectedPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
ACSS Performance Depth1 CSS depth issue(s) detectedPASS
Network Waterfall184 requests over 3344msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
d70shl7vidtft.cloudfront.net d70shl7vidtft.cloudfront.net | Other | 580ms | 18 KB | — | Kč72/mo | Costly |
These scripts may cost more than they're worth
- d70shl7vidtft.cloudfront.net adds 580ms and costs ~Kč72/month
d70shl7vidtft.cloudfront.net takes 580ms 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
Real-User Performance (CrUX)Field metrics from the Chrome User Experience ReportINFO
Chrome User Experience (CrUX)
Real-user metrics from the Chrome UX Report (2026-08-10 — 2026-09-06)
LCP (p75)
1144 ms
94% good
INP (p75)
171 ms
76% good
CLS (p75)
0.000
98% good
FCP (p75)
1090 ms
TTFB (p75)
591 ms
Image Optimization116 images, 1657 KB total, 18 KB wastedINFO
Image Optimization Audit
Total Images
116
Total Size
1657 KB
Oversized
2
Wasted
18 KB