51of 100
79of 100
www.rtdiamonds.jp
FLevel 2 · Slow
CLevel 4 · Fast
WordPress 7.1.2LiteSpeed CacheCloudflare
408msTTFB
51Lighthouse mobile · graded
4.7sLCP
0.02CLS
brCompression
HITCache
Lab data: Lighthouse 13.5.0 mobile run, graded above · Reproduce this run on PageSpeed Insights ↗
Real visitors · Chrome UX Report · mobile · this page or its site ·
fails Core Web Vitals
5.9sLCP (p75)
0.02CLS (p75)
Why is this different from the score in my browser?
This view grades the mobile run. Lighthouse 13.5.0 runs at Google through the PageSpeed Insights API on an emulated mid-range Android with a 4× CPU slowdown and a throttled connection. Chrome DevTools on your own machine, on the Desktop preset, applies almost none of that, and the same page routinely scores 30–50 points higher there. Neither number is wrong — they are different tests.
Mobile is what Google ranks on, so this is the number that affects your
search performance. To reproduce it, open the same run on PageSpeed Insights,
or pass strategy=mobile to the PageSpeed API — it defaults to desktop.
Lighthouse also varies a few points run to run on the same URL. Treat a trend across several scans as the signal, never a single digit.
Lab data: Google PageSpeed Insights (Lighthouse, mobile). Server probes (TTFB, compression, cache, headers) are measured separately from Vilnius, Lithuania (EU).
408msTTFB
51Lighthouse mobile
brCompression
HITCache
Lighthouse was unavailable for the desktop run · Mobile: 51 (F) —
Lab performance (Lighthouse)F41
1/5 checks passed · 16.2/40 pts Jump to section ↓
Server response & cachingD67
3/6 checks passed · 20/30 pts Jump to section ↓
Asset optimizationF40
1/5 checks passed · 8/20 pts Jump to section ↓
Platform & xSpeed readinessC75
1/2 checks passed · 6/8 pts Jump to section ↓
Top fixes ranked by points recovered · mobile
Top fixes ranked by points recovered · desktop
This is WordPress — the fixes below are one plugin away
- ✓WordPressWordPress 7.1.2
- →xSpeed Cache installedFree on wordpress.org — the setup wizard turns most of this report green.
- –MCP signal presentThe scan did not confirm MCP availability. Configure it in xSpeed → MCP Server, then verify authenticated access from an MCP client.
- –xSpeed Hub signalOptional: review Hub configuration and confirm authorized site membership at app.xspeedcache.com.
12 of these checks map to an xSpeed feature. Install the free xSpeed Cache plugin, connect its built-in MCP server, and your AI assistant can apply every fix and re-verify. If your AI already has access to the site (WP-CLI, SSH or hosting MCP), paste this:
My WordPress site www.rtdiamonds.jp scored 51/100 on xSpeed Scan (https://xspeedcache.com/scan/r/rtdiamonds-jp-e6b64df790). Install and activate the free xSpeed Cache plugin from wordpress.org/plugins/xspeed, run "wp xspeed mcp connect" and give me the MCP URL to paste into my AI client. Then read the failing checks from https://xspeedcache.com/scan/r/rtdiamonds-jp-e6b64df790.md and apply the fixes: enable page caching, compression, minification and lazy loading, warm the cache, and re-scan at https://xspeedcache.com/scan to confirm the score improved.Hosting is the other half.
xSpeed makes any host faster, but a cache is only as fast as the server behind a MISS.
xCloud — managed hosting from the team behind xSpeed — gives the cache an origin tuned for it, with agent/MCP access built in and bring-your-own-server pricing.
Explore xCloud.host →
Run this scan without the form
Plug xSpeed Scan into your agent stack, or test any site from a chat.
Connect this scanner to your AI assistant
Free. No API key, no sign-up. Scan any public site and get the same graded report as this one, with the fix for every failing check.
Endpoint
https://xspeedcache.com/scan/mcpClaude Code — one command
claude mcp add --transport http xspeed-scan https://xspeedcache.com/scan/mcpClaude Desktop, Cursor, or any MCP client — add to your config
{
"mcpServers": {
"xspeed-scan": {
"type": "http",
"url": "https://xspeedcache.com/scan/mcp"
}
}
}run_speed_scanScan any public URL and return this whole graded report.get_speed_scanRead a scan already run, by its id.
F
41/100
Lab performance (Lighthouse)
1/5 checks passed · 16.2/40 pts earned
Partial
Lighthouse performance score (mobile) 9.2/18 pts
51/100 (Lighthouse 13.5.0, mobile)
The composite Lighthouse score — every fix below moves it.
xSpeed Free
AI Optimize
AI prompt
Using my site's xSpeed MCP connection: run optimize_site, then run_benchmark to verify the score improved.Guidelines: Lighthouse performance scoring
Fail
Largest Contentful Paint ≤ 2.5s 0/8 pts
LCP 4.7s
Serve the hero content faster: cache the page, preload the LCP image, and ship critical CSS.
xSpeed Free
Page Cache + Preloader (Critical CSS in Pro)
AI prompt
Using my site's xSpeed MCP connection: enable page caching, start the preloader, and (on Pro) generate critical CSS for this page; then re-test LCP.Guidelines: web.dev — Largest Contentful Paint · Optimize LCP
Pass
Fail
Total Blocking Time ≤ 200ms 0/5 pts
TBT 698ms
Less JavaScript on the main thread: defer scripts and drop unused bundles.
xSpeed Free
JS Minify + Defer
AI prompt
Using my site's xSpeed MCP connection: enable JS minification and deferred loading, then re-test Total Blocking Time.Guidelines: web.dev — Total Blocking Time
Partial
First Contentful Paint ≤ 1.8s 2/4 pts
FCP 2.9s
First paint is gated on server response and render-blocking CSS.
xSpeed Free
Page Cache + CSS Minify
AI prompt
Using my site's xSpeed MCP connection: enable page caching and CSS minification, then re-test First Contentful Paint.Guidelines: web.dev — First Contentful Paint
D
67/100
Server response & caching
3/6 checks passed · 20/30 pts earned
Partial
Time to first byte ≤ 200ms 4/8 pts
TTFB 408ms measured from Vilnius, Lithuania (EU) (best of 2 requests). This includes the network round trips between us and your origin, not just server time. Google measured your server responding in 621ms from its own network — the gap between the two numbers is distance, not your server.
The server rebuilds the page on every request. A page cache answers in 5–15ms.
xSpeed Free
Page Cache
AI prompt
Using my site's xSpeed MCP connection: enable page caching and warm this page with the preloader, then re-check TTFB.Guidelines: web.dev — Time to First Byte
Pass
Page served from cache 7/7 pts
Cache HIT evidence in response headers
Guidelines: MDN — HTTP caching
Pass
HTML compression (Brotli/GZIP) 5/5 pts
Content-Encoding: br
Guidelines: MDN — Content-Encoding · RFC 7932 — Brotli
Fail
Efficient cache policy on static assets 0/5 pts
Fails the Lighthouse cache-policy audit — 8 files: 2.-PRINCESS-CUT-Photoroom-1.png, Gc-B2-Diamond-Shapes-Colorless1-Round-Brilliant-Cut-1-1.png, Gc-B2-Diamond-Shapes-Colorless10-Heart-Cut-1-1.png…
Give CSS/JS/images long Cache-Control lifetimes so repeat views are free.
xSpeed Free
Browser Cache
AI prompt
Using my site's xSpeed MCP connection: enable browser-cache headers for static assets, then re-run the audit.Guidelines: Lighthouse — Efficient cache policy
Pass
Partial
Clean redirect chain 1/2 pts
1 redirect(s) before the final URL: 301→https://www.rtdiamonds.jp/
Each redirect adds a full round-trip before the page can even start.
Guidelines: Lighthouse — Avoid redirects
F
40/100
Asset optimization
1/5 checks passed · 8/20 pts earned
Fail
No render-blocking resources 0/5 pts
Fails the Lighthouse audit — 8 files: styles.css, poppins.css, frontend.min.css… · ~3.0s of first paint
CSS/JS in <head> blocks first paint. Inline the critical CSS and defer the rest.
xSpeed Pro
Critical CSS + Unused CSS removal
AI prompt
Using my site's xSpeed MCP connection: generate critical CSS for the top pages and enable unused-CSS removal, then re-test.Guidelines: Lighthouse — Render-blocking resources
Partial
Minified CSS and JavaScript 2/4 pts
Lighthouse audit score 50% — 5 files: awesome.css, default.css, woocommerce.js…
Ship minified assets — whitespace and comments are pure transfer waste.
xSpeed Free
HTML/CSS/JS Minify
AI prompt
Using my site's xSpeed MCP connection: enable HTML, CSS and JS minification, purge the cache, and re-test.Guidelines: Lighthouse — Minify CSS · Minify JavaScript
Partial
Modern, optimized image formats 2/4 pts
Lighthouse audit score 50% — 8 files: 1764568017286-044606676b469abe6a4c-3281cab3821e443282ae684c2071d4c7-768x768.png.webp, 1764569549279-3380f6caa6366724d486-b2bf719a385f46e187f27e06e82f81a6-768x768.png.webp, JRT0017-Custom-768x768.jpg…
Serve WebP/AVIF at the right compression — usually the single largest byte saving.
xSpeed Pro
Image Converter (WebP/AVIF)
AI prompt
Using my site's xSpeed MCP connection: enable WebP/AVIF conversion with URL rewriting, then re-test image audits.Guidelines: Lighthouse — Modern image formats
Pass
LCP image discoverable early 4/4 pts
Passes the Lighthouse audit
Guidelines: web.dev — Optimize LCP · Lighthouse — LCP request discovery
Fail
Total page weight ≤ 1.5MB 0/3 pts
9.6MB transferred
Heavy pages are slow on every connection — compress, lazy-load, and trim.
xSpeed Free
Minify + Lazy Load + Image Converter (Pro)
AI prompt
Using my site's xSpeed MCP connection: enable minification and lazy loading (and image conversion on Pro), then re-check page weight.Guidelines: Lighthouse — Total byte weight
C
75/100
Platform & xSpeed readiness
1/4 checks passed · 6/8 pts earned
Info
Platform
WordPress detected (WordPress 7.1.2)
Informational.
Pass
Caching plugin active 4/4 pts
LiteSpeed Cache (X-LiteSpeed-Cache: hit)
Guidelines: WordPress.org — Optimization: caching
Partial
Powered by xSpeed 2/4 pts
Running LiteSpeed Cache instead
xSpeed bundles caching, minification, lazy-load, image optimization and an AI-controllable MCP server in one plugin — and imports settings from other caching plugins in one click.
xSpeed Free
xSpeed Migration (one-click import)
AI prompt
Install xSpeed and use its Migration tool to import your current caching settings, then deactivate the old plugin.Guidelines: xSpeed — feature overview · xSpeed vs other cache plugins
Info
xSpeed MCP route response not confirmed —
This scan did not confirm an xSpeed MCP route response. Client authentication and control were not tested.
Configure an MCP client for this endpoint and verify authenticated access before relying on it to inspect or change the site.
xSpeed Free
MCP Server (built into xSpeed Free)
AI prompt
In xSpeed → MCP Server, click Connect and paste the config into your AI client — then ask it to fix this report.Guidelines: Model Context Protocol · xSpeed documentation
B
80/100
Server response & caching
3/6 checks passed · 20/25 pts earned
Partial
Time to first byte ≤ 200ms 4/8 pts
TTFB 408ms measured from Vilnius, Lithuania (EU) (best of 2 requests). This includes the network round trips between us and your origin, not just server time.
The server rebuilds the page on every request. A page cache answers in 5–15ms.
xSpeed Free
Page Cache
AI prompt
Using my site's xSpeed MCP connection: enable page caching and warm this page with the preloader, then re-check TTFB.Guidelines: web.dev — Time to First Byte
Pass
Page served from cache 7/7 pts
Cache HIT evidence in response headers
Guidelines: MDN — HTTP caching
Pass
HTML compression (Brotli/GZIP) 5/5 pts
Content-Encoding: br
Guidelines: MDN — Content-Encoding · RFC 7932 — Brotli
Info
Efficient cache policy on static assets —
Needs the Lighthouse audit
Re-run when Lighthouse is available.
Guidelines: Lighthouse — Efficient cache policy
Pass
Partial
Clean redirect chain 1/2 pts
1 redirect(s) before the final URL: 301→https://www.rtdiamonds.jp/
Each redirect adds a full round-trip before the page can even start.
Guidelines: Lighthouse — Avoid redirects
C
75/100
Platform & xSpeed readiness
1/4 checks passed · 6/8 pts earned
Info
Platform
WordPress detected (WordPress 7.1.2)
Informational.
Pass
Caching plugin active 4/4 pts
LiteSpeed Cache (X-LiteSpeed-Cache: hit)
Guidelines: WordPress.org — Optimization: caching
Partial
Powered by xSpeed 2/4 pts
Running LiteSpeed Cache instead
xSpeed bundles caching, minification, lazy-load, image optimization and an AI-controllable MCP server in one plugin — and imports settings from other caching plugins in one click.
xSpeed Free
xSpeed Migration (one-click import)
AI prompt
Install xSpeed and use its Migration tool to import your current caching settings, then deactivate the old plugin.Guidelines: xSpeed — feature overview · xSpeed vs other cache plugins
Info
xSpeed MCP route response not confirmed —
This scan did not confirm an xSpeed MCP route response. Client authentication and control were not tested.
Configure an MCP client for this endpoint and verify authenticated access before relying on it to inspect or change the site.
xSpeed Free
MCP Server (built into xSpeed Free)
AI prompt
In xSpeed → MCP Server, click Connect and paste the config into your AI client — then ask it to fix this report.Guidelines: Model Context Protocol · xSpeed documentation
Recently scanned public reports All public scans →
Click anywhere or press Esc to close![Full-size screenshot]()