DarnlyResponsive checker: phone, tablet and desktop at once
Paste your page’s address and see it at 390, 768 and 1280 pixels wide, side by side. Scroll and click inside each one, just like the real thing.
Free from Darnly. Spot a bug in the app you're building? Darnly hands it to Claude Code, Codex or Cursor in one key.Add to Chrome
See a grey or blank box? That site blocks being shown inside other pages. It isn’t a problem with your layout.
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How it works
- Paste the address of your page. It needs to be live on the internet, starting with
https://. - See it at phone (390 px), tablet (768 px) and desktop (1280 px) widths side by side. Each view is the real page, so you can scroll and click inside it.
- Spot something broken? Use “Open at this width” to look closer, then tell your AI coding agent the width and what you see.
Questions
Why do some sites show as screenshots?
Many sites (Google, GitHub, Myntra, banks and most big apps) tell browsers not to show them inside other pages. That’s a safety setting on their side. For those sites we take real screenshots at each width instead, so you can still compare them. You can’t click inside a screenshot, so use “Open at this width” for a closer look.
Can I check my site on localhost?
No. This page runs on the internet, so it can’t see your computer. Deploy your site (a Vercel, Netlify or Cloudflare preview link works), then paste that address.
Is this the same as a real phone?
It shows the page at the same width a phone uses, which is what decides most layout problems. Touch, the on-screen keyboard and the phone’s own browser can still differ, so check on a real phone before you launch.
Why these three widths?
390 px is a modern iPhone, 768 px is an iPad held upright, and 1280 px is a common laptop. If a layout works at all three, it usually works in between too.
Is anything sent to Darnly?
Only the address you type. Our server checks whether the site allows being shown in a frame, and takes screenshots if it doesn’t. Live views load straight from your site into your browser.