The browser for ambitious web developers.
Build better websites in less time with a stand-alone browser that makes your site more responsive, more accessible and faster. Save hours on each project, love every minute of it.




Amazing developers from these companies use Polypane.
Everything you need in one developer tool.
Powerful devtools, multiple synced viewports, full-height screenshots, over two dozen debug tools, device and media query emulation, built-in live-reloading and more.
Responsive design
Mobile screens to 5K monitors, get all viewports in one overview.
Accessibility
Over 80 accessibility tests, 19 different simulators and 20+ debug tools.
Side by side
Dark and light, reduced motion, screen and print. No more manual switching!
Give it a try
Click, hover, scroll and type to see your actions happen in all panes.
to create amazing websites and webappsStart your free trial
to create amazing websites and webappsStart your free trial
to create amazing websites and webappsStart your free trial
Device sizes are not enough
You need a screen size wall.
When you focus on devices you miss the hundreds of screen sizes your real users use. Don't believe us? Check your own data. With Polypane's devices, CSS Breakpoint panes and freeform sizing you can get the real full overview.
All the viewports you need.
Don't manually resize and test websites screen-by-screen. Get all your viewports in one overview, no browser resizing needed.
Mobile screens, 5K monitors, all your CSS breakpoints or any size you want.
And they're all in sync.
Scrolling, clicking, typing and even hovers are synced across all viewports.
Don't test viewports or devices one-by-one, check them all at once.
Polypane helps with every aspect of web development.
Viewports, meta info, accessibility, performance, web vitals and media features, all easily testable. Fix issues before your users find them.
From A11y to Z-index
Apply over forty different debug tools to each viewport. Test your site in completely new ways.
Developers and designers love Polypane.
Here's what they say:
Polypane is easily one of the most useful tools for modern web designers and developers.

It is convenient seeing your work in multiple responsive views at the same time. Love it, 💯

This thing is FAST and the synchronized scrolling works amazingly. Prepare to be impressed.

Polypane is fast, helps me catch issues and the meta information preview is awesome.

Using Polypane and woah this is awesome! It’s really slick and fast! I was just 5 minutes in and I already fixed a bug.

I've started playing around with Polypane and 🤯. It has awesome debugging tools, accessibility checks and tests, and more. I'm really impressed.

Social media previews.
Pixel-perfect previews of social media sharing cards, for Twitter, Facebook, Slack, LinkedIn, Discord, Telegram and Google. In Dark and Light mode.
Dark mode media feature testing
No need to change your entire operating system! Test light and dark mode side-by-side in the same view. Also works for reduced motion, reduced data and even print styles.
Your favorite DevTools extensions
Install and use your favorite Chromium devtools, with support for React DevTools, Vue.js DevTools, Redux DevTools, Angular, Svelte and many more.

Plays well with all your favorite frameworks
Devtools extensions for your favorite JS frameworks and easy ways to prototype with your favorite CSS frameworks. Keep your stack, be more productive.
- React
- Vue
- Angular
- Svelte
- jQuery
- Tailwind CSS
- Bootstrap
- Foundation
- Bulma
…And that's just scratching the surface.
Polypane has everything you need to make awesome web experiences.
Build your next project with Polypane
- Use all features on all plans
- On Mac, Window and Linux
- 14-day free trial – no credit card needed

Frequently Asked Questions

Hi! 👋 I'm Kilian.
I'm the founder, developer, designer and support team at Polypane. Nice to meet you!
I built close to 200 websites in the past decade and I've always been building tools and libraries to improve my workflow. Polypane started as a prototype after getting frustrated that I had to resize my browser all the time. When I started using the prototype I was shocked: I instantly was 60% faster compared to just using Chrome.
And it's not just me. People keep telling me how much more efficient they are. 2 times, 3 times, some even 5 times as efficient!
That's why I'm building Polypane. My mission is to help devs and designers create the best web experiences they can, through a browser that puts them first. Wanna give it a try?
— Kilian Valkhof