Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
Info::
✓
Last-Modified header present
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
C
Image Optimization
Action
91 images, 0 KB saveable
REVIEW
91 images, 0 KB saveable
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cdn.prod.website-files.com/61477f2c24a8268... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
91images2.8 MB
0oversized-0 KB
54legacy format
15missing dimensionsCLS risk
Set explicit width and height to prevent CLS.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
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.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
i
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
B
Document Compression
Document response uses gzip; brotli would be ~20% smaller
REVIEW
Document response uses gzip; brotli would be ~20% smaller
Info::
i
Main HTML response uses gzip (brotli would be ~20% smaller)
All current browsers support brotli. Most CDNs (Cloudflare, Fastly, AWS CloudFront, Vercel, Netlify) can switch from gzip to brotli with a single config flag. Origin servers (nginx, Apache) need a brotli module compiled in -- nginx-brotli or Apache mod_brotli.
B
Asset Compression
2 of 6 asset hosts still on gzip
REVIEW
2 of 6 asset hosts still on gzip
Info::
✓
cdn.prod.website-files.com serves assets with brotli (assets: 215)
Got: cdn.prod.website-files.com (text/css)
Info::
i
unpkg.com serves assets with gzip; brotli would be ~20% smaller (assets: 6)
Every current browser accepts brotli. On a CDN this is a per-pull-zone toggle (Cloudflare, Fastly, CloudFront, CDN77, Bunny all expose it); on an origin it needs the brotli module (nginx-brotli, Apache mod_brotli). The saving lands on the assets this host serves, not on the HTML document -- the document's own encoding is reported separately.
Got: unpkg.com (text/css)
Info::
i
evs.cdp.clay.com serves assets with gzip; brotli would be ~20% smaller (assets: 5)
Every current browser accepts brotli. On a CDN this is a per-pull-zone toggle (Cloudflare, Fastly, CloudFront, CDN77, Bunny all expose it); on an origin it needs the brotli module (nginx-brotli, Apache mod_brotli). The saving lands on the assets this host serves, not on the HTML document -- the document's own encoding is reported separately.
Got: evs.cdp.clay.com (application/javascript)
Info::
✓
cdn.jsdelivr.net serves assets with brotli (assets: 4)
Got: cdn.jsdelivr.net (application/javascript)
Info::
✓
clay-webflow-dev.vercel.app serves assets with brotli (assets: 4)
Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.
B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
i
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW
Green Hosting
No green hosting detected
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
✓
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
5 fonts (464 KB)
PASS
5 fonts (464 KB)
Info::
i
5 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
5
464 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
6a1e067cbcc79b9f76bb28f...woff2swap
Size224 KB
Load time69 ms
Start433 ms
RiskFOUT — text flashes from fallback to web font
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
Phosphor.woff2woff2swap
Size144 KB
Load time100 ms
Start589 ms
RiskFOUT — text flashes from fallback to web font
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
i7dPIFZifjKcF5UAWdDRYEF...woff2swap
Size9 KB
Load time31 ms
Start745 ms
RiskFOUT — text flashes from fallback to web font
i7dMIFZifjKcF5UAWdDRaPp...woff2swap
Size9 KB
Load time34 ms
Start745 ms
RiskFOUT — text flashes from fallback to web font
66db6b52aca9770fe39fc77...woff2swap
Size77 KB
Load time37 ms
Start3.1 s
RiskFOUT — 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)
Fixing the unchecked items could save ~184 KB and ~368 ms
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
✓
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
✓
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
✓
No resource hint issues
A+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
✓
LCP image preload audit not available for this scan
A+
Server Response Intelligence
2 server-response signal(s) detected
PASS
2 server-response signal(s) detected
Info::
✓
`Vary` header declared: accept-encoding
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::
✓
`Last-Modified` present -- timestamp-based conditional GET supported
Consider also setting `ETag` for stronger revalidation -- ETags are content hashes that don't suffer from clock-skew or DST issues. Last-Modified alone is functional for conditional GETs and not a bug.
Network Waterfall
186 requests over 3831ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
63%of JavaScript execution is third-party
First-party Third-party2211ms · 1720KB · €38/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
clay-webflow-dev.vercel.app
clay-webflow-dev.vercel.app
Other
539ms
127 KB
69%
€9/mo
Costly
cdn.prod.website-files.com
cdn.prod.website-files.com
Other
435ms
127 KB
57%
€8/mo
Costly
jsDelivr
cdn.jsdelivr.net
CDN
163ms
29 KB
—
€3/mo
Optional
cdn.prod.website-files.com
cdn.prod.website-files.com
Other
145ms
1 KB
—
€3/mo
Optional
transcend-cdn.com
transcend-cdn.com
Other
123ms
51 KB
—
€2/mo
Optional
Google Tag Manager
www.googletagmanager.com
Tag Manager
119ms
169 KB
50%
€2/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
115ms
91 KB
34%
€2/mo
Optional
assets.clayrun.dev
assets.clayrun.dev
Other
100ms
3 KB
—
€2/mo
Optional
Facebook Pixel
connect.facebook.net
Advertising
92ms
110 KB
35%
€2/mo
Optional
jsDelivr
cdn.jsdelivr.net
CDN
83ms
444 KB
63%
€1/mo
Optional
cdn.claydar.com
cdn.claydar.com
Other
65ms
25 KB
—
€1/mo
Optional
cdn.prod.website-files.com
cdn.prod.website-files.com
Other
64ms
18 KB
—
€1/mo
Optional
cdn.intellimize.co
cdn.intellimize.co
Other
58ms
86 KB
65%
€1/mo
Optional
transcend-cdn.com
transcend-cdn.com
Other
57ms
90 KB
42%
€1/mo
Optional
www.gstatic.com
www.gstatic.com
Other
52ms
348 KB
71%
€1/mo
Optional
clay-webflow-dev.vercel.app
Other
Costly
Execution539ms
Transfer127 KB
Unused69%
Monthly Cost€9/mo
cdn.prod.website-files.com
Other
Costly
Execution435ms
Transfer127 KB
Unused57%
Monthly Cost€8/mo
jsDelivr
CDN
Optional
Execution163ms
Transfer29 KB
Monthly Cost€3/mo
cdn.prod.website-files.com
Other
Optional
Execution145ms
Transfer1 KB
Monthly Cost€3/mo
transcend-cdn.com
Other
Optional
Execution123ms
Transfer51 KB
Monthly Cost€2/mo
Google Tag Manager
Tag Manager
Optional
Execution119ms
Transfer169 KB
Unused50%
Monthly Cost€2/mo
Facebook Pixel
Advertising
Optional
Execution115ms
Transfer91 KB
Unused34%
Monthly Cost€2/mo
assets.clayrun.dev
Other
Optional
Execution100ms
Transfer3 KB
Monthly Cost€2/mo
Facebook Pixel
Advertising
Optional
Execution92ms
Transfer110 KB
Unused35%
Monthly Cost€2/mo
jsDelivr
CDN
Optional
Execution83ms
Transfer444 KB
Unused63%
Monthly Cost€1/mo
cdn.claydar.com
Other
Optional
Execution65ms
Transfer25 KB
Monthly Cost€1/mo
cdn.prod.website-files.com
Other
Optional
Execution64ms
Transfer18 KB
Monthly Cost€1/mo
cdn.intellimize.co
Other
Optional
Execution58ms
Transfer86 KB
Unused65%
Monthly Cost€1/mo
transcend-cdn.com
Other
Optional
Execution57ms
Transfer90 KB
Unused42%
Monthly Cost€1/mo
www.gstatic.com
Other
Optional
Execution52ms
Transfer348 KB
Unused71%
Monthly Cost€1/mo
These scripts may cost more than they're worth
clay-webflow-dev.vercel.app adds 539ms and costs ~€9/month
cdn.prod.website-files.com adds 435ms and costs ~€8/month
63% of JavaScript execution time comes from third-party scripts.
Why this matters
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
clay-webflow-dev.vercel.app takes 539ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
69% of clay-webflow-dev.vercel.app's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
cdn.prod.website-files.com takes 435ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
57% of cdn.prod.website-files.com's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
50% of Google Tag Manager's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
63% of jsDelivr's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
65% of cdn.intellimize.co's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
71% of www.gstatic.com's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.