Alternatives to Sizzy
Developer browser with synced device previews and project workspaces. The listings below can replace it for an important use case. Each note says what changes if you switch.
The original
Sizzy
Developer browser with synced device previews and project workspaces.
Replacements
Listings that take over the same core job as Sizzy.
Responsively App
Developer browser that renders many device viewports side by side.
Responsively App is free and open source under AGPL-3.0 and mirrors interactions across viewports, but it is an Electron app with a large memory footprint and no project workspaces.
Polypane
Multi-viewport browser with accessibility and performance tooling built in.
Polypane is also a paid Chromium-based multi-viewport browser, and it adds built-in accessibility simulation, performance tooling and live CSS editing across synchronised panes.
Blisk
Cross-device testing browser with hot reload and synced scrolling.
Blisk has a free tier with daily usage limits, reloads automatically on file changes and includes screenshot and recording tools for bug reports, still using Chromium rendering only.
LT Browser
A desktop browser for building, testing and debugging responsive websites across many device viewports side by side.
LT Browser is freemium, offers more than 50 device presets side by side and works with sites that block iframes, but it is tied to a commercial testing platform.
Similar software
Related functionality, not a direct replacement.
BrowserStack Live
A cloud service for testing websites by hand in real desktop and mobile browsers on real devices.
TestMu AI
A cloud testing platform, formerly LambdaTest, for cross-browser, automated and AI-assisted testing of web apps.
Chrome DevTools
The web developer tools built into Google Chrome for editing pages, debugging and profiling performance.
Firefox Developer Edition
A pre-release build of Firefox for web developers, with the newest developer tools and platform features.
