SEO UTILITIES
Screen Resolution Simulator — Preview Site Sizes
Preview how a webpage looks at different screen resolutions in an iframe. Check responsive layouts across desktop, tablet, and mobile widths, free.
Your files never leave your device.
Some sites refuse to be embedded (X-Frame-Options) and will show blank here — that's the target site's policy, not a bug.
This simulator loads a webpage inside a resizable frame set to common screen resolutions, so you can see how a responsive layout adapts from a wide desktop down to a phone width without owning every device. It's a quick sanity check on whether your breakpoints behave — but read the honest limitations below before you rely on it.
How to use it
- Enter the URL of the page you want to preview.
- Pick a resolution or width to load the page inside the frame.
- Switch between sizes and watch how the layout reflows.
Troubleshooting
- The site won't load — the frame is blank or shows an error.
- Many sites send an X-Frame-Options or Content-Security-Policy frame-ancestors header that forbids being embedded in another page (a clickjacking defence). When they do, the browser blocks the frame and there is no workaround from a tool — it's the site's own security choice.
- A private staging site won't preview.
- The URL has to be reachable by your browser. A local dev URL works if you're on the same machine and it isn't blocking frames; a staging site behind a login generally won't load.
Frequently asked questions
- Is this the same as testing on a real device?
- No. It approximates the viewport width, which catches most layout issues, but real devices differ in pixel density, touch behaviour, browser quirks, and performance. Use it for a fast first pass, then verify critical pages on actual hardware.
- Does it simulate touch and mobile browser features?
- It simulates the screen dimensions, not the full device. For touch events and mobile rendering, use your browser's built-in device mode or a real phone.