https://kling4ai.app
Performance
· 27 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.SCORE
96
GRADE
A
FIX
1
REVIEW
1
PASS
21
INFO
4
Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
63
96
96
100
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
4.30 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
5.41 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
288 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.
4.30 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.
5.62 s
Page Load Progression
578 ms 1.2 s
1.7 s
2.3 s
2.9 s 3.5 s 4.0 s
4.6 sChecks
2721 PASS 1 REVIEW 1 FIX
DJS Execution CostAction3219ms total JS executionFIX
JS Execution Cost
Action3219ms total JS execution
3219ms total JS execution
Warning::
https://kling4ai.app/: 1414ms CPU time
Warning::
https://kling4ai.app/assets/framework-DJH1pfSr.js: 937ms CPU time
Warning::
Unattributable: 590ms CPU time
Info::
https://static.cloudflareinsights.com/beacon.min.j...: 178ms CPU time
Info::
https://kling4ai.app/assets/video-studio-hero-0Yh6...: 100ms CPU time
Info::
Third-party scripts: 178ms (6% of total)
Main Thread Breakdown
Other 36% Script Evaluation 32% Style & Layout 22% Rendering 5%
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://kling4ai.app/ | 1414ms | 73ms | 38ms | 1st |
| https://kling4ai.app/assets/framework-DJH1pfSr.js | 937ms | 688ms | 9ms | 1st |
| Unattributable | 590ms | 54ms | 0ms | 1st |
| https://static.cloudflareinsights.com/beacon.min.js/v31edd6df95cf4e85bb4c19e7a9bdbcba1788362987495 | 178ms | 154ms | 1ms | 3rd |
| https://kling4ai.app/assets/video-studio-hero-0Yh6hP1g.js | 100ms | 80ms | 0ms | 1st |
BHTTP Cachingpublic, max-age=0, s-maxage=60, must-revalidateREVIEW
HTTP Caching
public, max-age=0, s-maxage=60, must-revalidate
public, max-age=0, s-maxage=60, must-revalidate
Info::
Cache-Control header is set
Got: public, max-age=0, s-maxage=60, must-revalidate
Info::
CDN TTL: 1 minute (s-maxage=60)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control
public, max-age=0, s-maxage=60, must-revalidate
| Directive | Value | Meaning |
|---|---|---|
| public | — | Any cache may store this response |
| max-age | 0 | Cache for 0 seconds |
| s-maxage | 60 | CDN caches for 1 minute |
| must-revalidate | — | Must recheck with server after expiry |
A+Page Weight Budget386 KB transferred, 88 requestsPASS
Page Weight Budget
386 KB transferred, 88 requests
386 KB transferred, 88 requests
Info::
Page weighs 1.3 MB (386 KB transferred)
Info::
88 HTTP requests
Info::
Estimated 0.08 g CO2 per page load
386 KB transferred
88 requests
0.08 g CO2 per page load
JavaScript 223.2 KiB 58%
HTML 41.3 KiB 11%
Other 33.4 KiB 9%
CSS 32.2 KiB 8%
Images 27.9 KiB 7%
Fonts 21.0 KiB 5%
Other 3.9 KiB 1%
Other 1.3 KiB 0%
Other 949 B 0%
Other 923 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Under budget
A+Third-Party Impact4% third-party, 0 ms blockingPASS
Third-Party Impact
4% third-party, 0 ms blocking
4% third-party, 0 ms blocking
Info::
Third-party code accounts for 4% of page weight (16.3 KiB of 386.1 KiB)
Info::
Third-party blocking time is low (0 ms)
96%
First-party Third-party
A+Text CompressionAll text resources are compressedPASS
Text Compression
All text resources are compressed
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+Image Optimization3 images, 0 KB saveablePASS
Image Optimization
3 images, 0 KB saveable
3 images, 0 KB saveable
Info::
All images are well-optimized
3 images 27 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+Font Loading2 fonts (21 KB)PASS
Font Loading
2 fonts (21 KB)
2 fonts (21 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
2
21 KB total
Render-blocking
0
of 2
Dominant font-display
swap
Most common across fonts
Font loading timeline
Transfer FOIT (block) FOUT (swap)
outfit-19c86109.woff2 woff2 swap
Size 7 KB
Load time 45 ms
Start 51 ms
Risk FOUT — text flashes from fallback to web font
outfit-be21ba2a.woff2 woff2 swap
Size 14 KB
Load time 102 ms
Start 52 ms
Risk FOUT — text flashes from fallback to web font
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+JS Bundles64 scripts, 0 KB unusedPASS
JS Bundles
64 scripts, 0 KB unused
64 scripts, 0 KB unused
0 KB unused JavaScript
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://kling4ai.app/assets/global-error-CVl8f3Cz.js | 1 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/framework-DJH1pfSr.js | 60 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/rolldown-runtime-QTnfLwEv.js | 1 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/url-utils-BQKFb685.js | 1 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/error-Cw7PdD78.js | 1 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/navigation-jMN0Yddo.js | 2 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/react-DlbkFqaW.js | 14 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/BaseLink-H_zw-cXa.js | 6 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/locale-Cc3baYjD.js | 3 KB | — | ✓ | 1st |
| https://kling4ai.app/assets/welcome-copy-DIyE0o41.js | 2 KB | — | ✓ | 1st |
A+Resource CachingAll resources properly cachedPASS
Resource Caching
All resources properly cached
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+Critical Rendering PathNo render-blocking resourcesPASS
Critical Rendering Path
No render-blocking resources
No render-blocking resources
Info::
No render-blocking resources detected
A+Resource Hints4 hints, 0 missing preconnectsPASS
Resource Hints
4 hints, 0 missing preconnects
4 hints, 0 missing preconnects
Info::
Page uses 4 resource hint(s)
Current Resource Hints
preconnect—
preload 4
dns-prefetch—
prefetch—
4 resource hints configured
A+HTTP/3 (QUIC)HTTP/3 advertised via Alt-SvcPASS
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
HTTP/3 advertised via Alt-Svc
Info::
HTTP/3 (QUIC) is supported
First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.
A+Document CompressionDocument response uses brotliPASS
Document Compression
Document response uses brotli
Document response uses brotli
Info::
Main HTML response uses brotli (Content-Encoding: br)
Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.
A+LCP Image PreloadLCP preload audit not availablePASS
LCP Image Preload
LCP preload audit not available
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+Main HTML Cache-ControlMain HTML max-age=0 (≤ 5min) is appropriatePASS
Main HTML Cache-Control
Main HTML max-age=0 (≤ 5min) is appropriate
Main HTML max-age=0 (≤ 5min) is appropriate
Info::
Main HTML max-age=0 (≤ 5min) is appropriate
Got: public, max-age=0, s-maxage=60, must-revalidate
A+Server-Timing Observability3 Server-Timing entries advertisedPASS
Server-Timing Observability
3 Server-Timing entries advertised
3 Server-Timing entries advertised
Info::
Server-Timing header advertises 3 timing entries
A+Server Response Intelligence2 server-response signal(s) detectedPASS
Server Response Intelligence
2 server-response signal(s) detected
2 server-response signal(s) detected
Info::
`Vary` header declared: RSC, Accept, Next-Router-State-Tree, Next-Router-Prefetch, Next-Router-Segment-P...
The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).
Info::
No `ETag` or `Last-Modified` -- conditional GET not supported
Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.
A+Page Weight Inventory88 resources · 386 KB · 0 KB savings availablePASS
Page Weight Inventory
88 resources · 386 KB · 0 KB savings available
88 resources · 386 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 386 KB
Info::
8 third-party resources (4% of weight)
88 resources · 386.1 KiB · 8 third-party Within 1MB page-weight target
JavaScript 58% · 223.2 KiB
Image 16% · 61.4 KiB
Document 11% · 41.3 KiB
CSS 8% · 32.2 KiB
Font 5% · 21.0 KiB
Other 2% · 7.1 KiB
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 88 resources | 386.1 KiB | ||||||
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
Render-Blocking Resources
No render-blocking resources detected
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+Third-Party ResourcesNo third-party resources detectedPASS
Third-Party Resources
No third-party resources detected
No third-party resources detected
A+JavaScript BlockingNo render-blocking JS or document.write usage detectedPASS
JavaScript Blocking
No render-blocking JS or document.write usage detected
No render-blocking JS or document.write usage detected
Info::
No JavaScript blocking issues detected
ACSS Performance Depth1 CSS depth issue(s) detectedPASS
CSS Performance Depth
1 CSS depth issue(s) detected
1 CSS depth issue(s) detected
Warning::
1 `@font-face` rule(s) without `font-display` -- causes FOIT
An `@font-face` rule without `font-display` causes Flash of Invisible Text (FOIT): the browser hides the styled text for up to 3 seconds while the custom font downloads, then either swaps to fallback (Chrome / Firefox) or stays invisible (older Safari). Add `font-display: swap` (shows fallback immediately, swaps in the custom font when ready) or `font-display: optional` (uses fallback if the font isn't ready in 100ms; never causes visible swap). Either eliminates FOIT outright.
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Asset CompressionNo text asset hosts to measureINFO
Asset Compression
No text asset hosts to measure
No text asset hosts to measure
Info::
No third-party or subdomain host served enough text assets to measure
Asset compression is measured per host, from one HEAD request against a sampled resource. Pages that serve all their JS and CSS from the document's own origin are covered by the document compression check instead.
Network Waterfall88 requests over 2307msINFO
Network Waterfall
88 requests over 2307ms
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
6% of JavaScript execution is third-party
First-party Third-party 178ms · 10KB · €1/mo
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
static.cloudflareinsights.com static.cloudflareinsights.com | Other | 178ms | 10 KB | — | €1/mo | Optional |
static.cloudflareinsights.com
Other
Execution 178ms
Transfer 10 KB
Monthly Cost €1/mo
Image Optimization4 images, 28 KB total, 0 KB wastedINFO
Image Optimization
4 images, 28 KB total, 0 KB wasted
Image Optimization Audit
Total Images
4
Total Size
28 KB
1 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.