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Responsive testing Chrome extension
Free responsive testing Chrome extension for multi-device website previews with sync scroll and device frames.
Why MSIM
MSIM is a free Chrome extension for responsive testing. Open any site tab, pick devices, and compare layouts side-by-side without constant DevTools resizing.
Key benefits
- Find responsive bugs in seconds
- Compare multiple devices side-by-side
- Validate mobile layouts before deployment
- Reduce repetitive DevTools switching