DarnlyPage speed checker: why is my site slow?
Paste your site to get phone and laptop scores, watch it load frame by frame, and get the three fixes that matter most, as prompts for your AI agent.
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Example result
Google is loading your page on a phone and a laptop…
How it loads on a phone
What a visitor sees while they wait. The highlighted frame is when your main content appears.
Core Web Vitals, in plain words
Top 3 fixes
Nothing big left to fix. Nice work.
Details: every number Google measured
| Measure | Phone | Laptop |
|---|
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How it works
- Paste your site’s address. Google loads it on a mid-range phone and on a laptop, which takes 15 to 40 seconds.
- See your score for each, and watch the page load frame by frame, so you can see exactly what visitors stare at while they wait.
- Read the three things that matter (how fast the main content appears, whether the page jumps, how fast taps answer) in plain words, then copy one prompt that fixes the top three problems.
Questions
Where do the scores come from?
From Google PageSpeed Insights, the same Lighthouse test Google shows at pagespeed.web.dev. We run it for you on a phone and a laptop and turn the result into plain words and prompts for your AI agent.
Why is my phone score so much lower?
Google tests phones on a slow 4G connection with a mid-range processor, because that’s what many real visitors have. Big images and lots of JavaScript hurt much more there than on your laptop.
What are Core Web Vitals?
Three numbers Google uses to judge how a page feels: Largest Contentful Paint (how long the biggest image or text takes to appear; good is under 2.5 seconds), Cumulative Layout Shift (how much the page jumps while loading; good is under 0.1) and Interaction to Next Paint (how fast taps and clicks answer; good is under 200 ms).
Why does the score change each time I test?
Every test loads your site over a real network, so server speed, ads and third-party scripts vary a little each time. A swing of 5 to 10 points is normal. Results are kept for an hour, so testing again within the hour shows the same result.
Can I test a site on localhost?
No. Google tests from the internet, so the site needs a public address. Deploy a preview (Vercel, Netlify and Cloudflare all make one per branch), then paste that.
Is 100 the goal?
No. Above 90 is great, and 50 to 89 is fine for most sites. Fix the red items first: they’re what visitors actually feel.