Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
94
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
662 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.75 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.
0.002
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.00 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.
1.77 s
Page Load Progression
375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
22
12 PASS7 REVIEW
B
Page Weight Budget
1.5 MB transferred, 52 requests
REVIEW
1.5 MB transferred, 52 requests
Info::
✓
Page weighs 1.7 MB (1.5 MB transferred)
Warning::
!
Images are 1.4 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.4 MB
Info::
i
52 HTTP requests
Info::
i
Estimated 0.31 g CO2 per page load
1.5 MBtransferred
52 requests
0.31 g CO2 per page load
Images1.4 MiB94%
Fonts47.0 KiB3%
HTML46.2 KiB3%
CSS1.2 KiB0%
Other1.0 KiB0%
JavaScript798 B0%
02.4 MB4.9 MB
Under budget
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Why this matters
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
C
Image Optimization
Action
22 images, 0 KB saveable
REVIEW
22 images, 0 KB saveable
Warning::
!
https://www.amadohastaelextremo.es/assets/images/i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.amadohastaelextremo.es/assets/images/i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.amadohastaelextremo.es/assets/images/i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.amadohastaelextremo.es/assets/images/i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.amadohastaelextremo.es/assets/images/i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://www.amadohastaelextremo.es/assets/images/i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
22images1.4 MB
0oversized-0 KB
16legacy format
6missing 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
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
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.
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+
Main HTML Cache-Control
Main HTML max-age=0 (≤ 5min) is appropriate
PASS
Main HTML max-age=0 (≤ 5min) is appropriate
Info::
✓
Main HTML max-age=0 (≤ 5min) is appropriate
Got: max-age=0
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.
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
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
52 requests over 895ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Image Optimization
43 images, 494 KB total, 290 KB wasted
INFO
Image Optimization Audit
Total Images
43
Total Size
494 KB
Oversized
5
Wasted
290 KB
1 missing alt text43 missing dimensions37 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.
