Responsive Tester
Preview a website at a chosen device width
About
Preview a website at common device widths — phones, tablets, and desktops — to check responsive layouts. Enter a URL, pick one or more device presets, and view the site at each width. Everything runs in your browser; the URL loads directly into sandboxed iframes.
About this tool
Preview any URL at phone, tablet and desktop widths. Quick multi-viewport responsive check. Free, client-side, no signup. Responsive Tester runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- Responsive Tester is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use Responsive Tester?
Open Responsive Tester, enter or paste your input, and copy the result. The page works without an account.
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