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Responsive Website Tester

Fast, colorful, and browser-only. Try different device sizes, rotate, and capture screenshots.

How to use

Website URL

Tip: screenshots of cross-origin sites are restricted by browsers (see note).

Device Presets Auto (responsive) iPhone 13 — 390×844 Pixel 6 — 412×915 iPad — 768×1024 Tablet — 820×1180 Desktop — 1366×768 Large Desktop — 1920×1080

Orientation

Width: 100%

Overlays & Helpers

Custom CSS (applies only to same-origin sites)

Presets

Presets are stored in your browser (localStorage).

Auto

Preview area — sandboxed iframe

Cross-origin note:

May restrict screenshots

360

768

1024+

Rendered using your browser engine.

How it works

1. Enter a URL and press Load. The site appears in the sandboxed iframe.
2. Use device presets or drag the width slider to test breakpoints. Rotate to swap width/height.
3. Capture uses html2canvas. Most cross-origin pages block pixel reading — the tool will warn if screenshot is impossible.
4. Custom CSS can be applied only if the page shares the same origin (browser security).