SplitQA – Compare Sites, mirror actions & screen sizes in real time

Responsive QA for two sites at once. SplitQA locks your local build and your live site to the same screen size: drag one handle and both resize together, like Chrome DevTools' responsive mode for two sites at once. Scrolling, page navigation and even mouse actions can stay in sync, so you can spot what changed between them at every breakpoint. Built for front-end developers, QA testers and anyone migrating or redesigning a website. Looking for a general split-screen or tab-tiling tool? SplitQA isn't one. It's a testing tool for comparing two versions of a site at identical screen sizes. FEATURES • One shared width handle: drag it, type a width, or pick a preset (320–1920px) • Fit to screen: wide layouts scale down visually while the sites still see the real width, so media queries behave correctly • Sync scroll: match by pixel or by percentage of page height • Sync pages: click a link on one side and the other loads the same path on its own domain (works with single-page apps too) • Mirror mouse: replay hovers and clicks from one pane on the other, including CSS hover menus (off by default) • Hide scrollbars: overlay-style, like DevTools device mode • Remembers your URLs, width and settings HOW TO USE 1. Click the SplitQA toolbar icon. 2. Enter your local URL (e.g. localhost:3000) on the left and your live URL on the right. 3. Drag the handle or pick a preset. PRIVACY SplitQA has no servers and collects no data. Everything runs in your browser, and your URLs and settings are stored locally on your device. GOOD TO KNOW • SplitQA isn't full device emulation: it doesn't change the user agent or emulate touch. • Some pages refuse to run inside a frame (e.g. Google sign-in, some payment pages). Use the ↗ button to open a pane in a normal tab.