Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
C
Image Optimization
Action
40 images, 0 KB saveable
REVIEW
40 images, 0 KB saveable
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAC4A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAh0A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADgA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAh0A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://vipcarpetcleaninglondon.co.uk/wp-content/u... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://vipcarpetcleaninglondon.co.uk/wp-content/t... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAArgA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAh8A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://vipcarpetcleaninglondon.co.uk/wp-content/u... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADwA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAi4A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAh4A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAV0A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAh0A... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADIA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://vipcarpetcleaninglondon.co.uk/wp-content/t... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAiIA... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
40images292 KB
0oversized-0 KB
13legacy format
17missing 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
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
Main HTML Cache-Control
No Cache-Control header on main HTML response
REVIEW
No Cache-Control header on main HTML response
Info::
i
Main HTML response has no Cache-Control header
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.
B
JavaScript Blocking
2 JS blocking issue(s) detected
REVIEW
2 JS blocking issue(s) detected
Warning::
!
5 render-blocking <script src> tag(s) without async/defer
Each `<script src=...>` without `async`, `defer`, or `type="module"` blocks HTML parsing while the browser fetches and executes it. The block lasts the entire round-trip + execution time -- on slow networks this translates directly into LCP delay. Add `defer` (executes after parse, in source order) for scripts that interact with the DOM, or `async` (executes whenever ready) for analytics / independent scripts. Module scripts (`type="module"`) are deferred by default.
Warning::
!
Total JS execution time is 8.8 s -- over the 3.5s budget
Total JavaScript execution (parse + compile + run) across all scripts exceeds 3.5 seconds. On low-end devices that becomes 7-15+ seconds and shows up directly in TBT and INP. Reduce by: tree-shaking unused dependencies, code-splitting (dynamic `import()`), removing or deferring third-party tracking, and replacing heavy frameworks where they're not needed.
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
9 fonts (283 KB)
PASS
9 fonts (283 KB)
Info::
i
9 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
9
283 KB total
Render-blocking
0
of 9
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
pxiByp8kv8JHgFVrLCz7Z1x...woff2swap
Size8 KB
Load time157 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
pxiEyp8kv8JHgFVrJJfecg....woff2swap
Size8 KB
Load time165 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
fontawesome-webfont.woff2unknownswap
Size1 KB
Load time936 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
pxiByp8kv8JHgFVrLEj6Z1x...woff2swap
Size8 KB
Load time151 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
pxiByp8kv8JHgFVrLDz8Z1x...woff2swap
Size8 KB
Load time145 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
1Ptug8zYS_SKggPNyC0ITw....woff2swap
Size46 KB
Load time195 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
SegoePrint.woff2woff2swap
Size75 KB
Load time58 ms
Start1.7 s
RiskFOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size34 KB
Load time111 ms
Start2.5 s
RiskFOUT — text flashes from fallback to web font
fontawesome-webfont.woffwoffswap
Size96 KB
Load time356 ms
Start2.6 s
RiskFOUT — text flashes from fallback to web font
Convert to woff2 for ~30% smaller file size
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 ~29 KB and ~58 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
3 hints, 0 missing preconnects
PASS
3 hints, 0 missing preconnects
Info::
✓
Page uses 3 resource hint(s)
Current Resource Hints
preconnect
1
preload—
dns-prefetch
2
prefetch—
3 resource hints configured
A+
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
PASS
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 Compression
Document response uses brotli
PASS
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 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::
i
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.
Each `<link rel="stylesheet">` without a non-blocking `media` attribute holds up the first paint. Browsers download all of them before painting any content. Consolidate into 1-2 critical-path stylesheets; defer non-critical CSS via `<link rel="stylesheet" media="print" onload="this.media='all'">` or via the loadCSS pattern; inline above-the-fold CSS in `<style>` to short-circuit the request entirely.
Asset Compression
No text asset hosts to measure
INFO
No text asset hosts to measure
Info::
i
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 Waterfall
127 requests over 5863ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
72%of JavaScript execution is third-party
First-party Third-party6367ms · 913KB · £33/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
universe-static.elfsightcdn.com
universe-static.elfsightcdn.com
Other
3893ms
462 KB
45%
£20/mo
Costly
www.gstatic.com
www.gstatic.com
Other
1779ms
0 KB
46%
£9/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
268ms
196 KB
40%
£1/mo
Costly
PayPal
www.paypal.com
Payment
182ms
101 KB
69%
£1/mo
Essential
Google Tag Manager
www.googletagmanager.com
Tag Manager
150ms
133 KB
53%
£1/mo
Optional
Stripe
js.stripe.com
Payment
96ms
21 KB
—
£0/mo
Essential
universe-static.elfsightcdn.com
Other
Costly
Execution3893ms
Transfer462 KB
Unused45%
Monthly Cost£20/mo
www.gstatic.com
Other
Costly
Execution1779ms
Transfer0 KB
Unused46%
Monthly Cost£9/mo
Google Tag Manager
Tag Manager
Costly
Execution268ms
Transfer196 KB
Unused40%
Monthly Cost£1/mo
PayPal
Payment
Essential
Execution182ms
Transfer101 KB
Unused69%
Monthly Cost£1/mo
Google Tag Manager
Tag Manager
Optional
Execution150ms
Transfer133 KB
Unused53%
Monthly Cost£1/mo
Stripe
Payment
Essential
Execution96ms
Transfer21 KB
Monthly Cost£0/mo
These scripts may cost more than they're worth
universe-static.elfsightcdn.com adds 3893ms and costs ~£20/month
www.gstatic.com adds 1779ms and costs ~£9/month
Google Tag Manager adds 268ms and costs ~£1/month
72% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
Why this matters
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
universe-static.elfsightcdn.com takes 3893ms 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
www.gstatic.com takes 1779ms 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
Google Tag Manager takes 268ms 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 PayPal'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
53% 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.