How developers build responsive & accessible websites. 82× faster.
A standalone browser to guide your web development workflow every step of the way. Built-in tools for responsive design, accessibility, meta information and so much more.




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.
Viewport Sizes
Mobile screens to 5K monitors, get all viewports in one overview.
Accessibility
Over 80 accessibility tests, 14 different emulators and two dozen 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
Polypane helps with every aspect of web development.
Get the full overview of viewports, meta info, accessibility issues and media features. Fix issues before they happen.
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.
From A11y to Z-index
Apply over two dozen 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.

Polypane is a smart design environment where you can preview your designs across devices and viewports.

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 query 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.

Live and hot reloading.
Zero configuration live reloading for anything from plain old HTML to Wordpress to React or Vue. Images and CSS are updated without a page refresh.
Plays well with all your favorite frameworks
Devtools extensions for your favorite JavaScript frameworks and easy ways to prototype with your favorite CSS frameworks. Keep your stack, become 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
- Try all plans, all features
- On Mac, Window and Linux
- 14-day free trial – no credit card needed


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.
- Kilian Valkhof