Polypane. For devs who care

@polypane.app

2108 Followers 2064 Following

The missing half of your development environment. Chromium-based workspace for building great websites. Built for web developers who care | Try out for free at https://polypane.app | By @kilianvalkhof.com

"Overlay behavior. The helper adds a button to local URLs. You can configure additional rules for specific domains." What follows is three images showing the button, overlay and auto-open styles along with instructions.
Polypane showing a directory listing page across three panes
Polypane cycling through the demos mentioned in the article.
Four stacked cheat sheets on a table.
Meta data overview of the CSS website with a "text-scale" entry.
A table with cards, stickers and other things on it. Behind that is a monitor showing Polypane and a large banner with the Polypane logo.
Top right corner of a browser. A half circle with an arrow pointing out is visible on the side
A browser with a Polypane button in the top right
Polypane elements panel with a red "quirks mode" badge in place of a doctype.
Polypane, shown grayed out with a popup centered on top of it, titled "Sign in" and saying "touch ID to use passkey".
Social media preview of Polypane.app as shared on Whatsapp
Polypane showing the quick start page and a popover listing a number of css media features. The top one says "prefers-reduced-pungency" and the value "remove" is selected.
Part of the Polypane Elements UI. The style tab is selected listing ":hover" and ":focus" lines with switches. The hover switch is turned on.
a complex flex-wrapped layout with dozens of items. The entire element is highlighted with all the spacing between elements rendered with a flex-gap visualisation.
AI Business Excellence Awards Most Innovative Web Developer Browser Polypane
A man and a woman viewing two laptops. We see the covers of the laptops and one of them is covered in stickers by Polypane, Fronteers, NL Design System and more.
a context menu on a header, showing a list of options like "inspect element" and "reload this pane". The cursor is on a highlighted item named "Copy link to document fragment".
The Polypane elements panel showing a 'debug' tab with multiple CSS properties and contexts. There is a bright pink arrow overlaid pointing to the 'stacking context parent', showing a DOM element.
Capterra shortlist 2026, Software Advice Frontrunners 2026, Polypane
List of meta info. Security.txt has a warning icon and the text "Expires in 22 days" behind it.
Security.txt Expired: The Expires date in this Security.txt is in the past
A screen showing Polypane, slightly out of focus. In front of it, a hand hold a small rectangular device with nine buttons in, all showing the Polypane icon together with various title like "workspace 1", "horizontal layout" and "reload".
Polypane homepage with an opened menu below the site icon titled "Brand kit"
A magazine folded open showing an article with the title ‘a browser just for developers’
Two badges with the names: GetApp Category leaders 2025 Capterra shorrtlist 2025 With the Polypane logo below them
Polypane showing two mobile panes showing sarajoy.dev. The elements panel is visible, and an HTML comment showing an ASCII representation of Sara is visible.
Polypane elements panel autocompleting "C" to "Color"
Part of the Polypane Elements panel with a div selected, focused on the "A11y" tab. The "accessible name" and "aria-label" fields are highlighted and both have an error message. The "Accessible name" error reads "Elements with a generic role having an accessible name is not broadly supported by screen readers" and the "aria-label" error reads "Elements with generic role can't have an aria-label".
A table filled with Polypane stickers and licorice
yucca_tory, 5d ago, Designer/Developer "I will happily shill for Polypane all day every day. The amount of debugging you can do in the tool makes me want to cry with joy. It makes testing almost enjoyable. It's one of those things that if Kilian doubled the price, I'd still gladly pay it because it makes my life so much easier."
the Polypane Outline Panel. "Show potentials" is checked and has a big arrow pointing to it. In the outline, greyes-out sections are visible with the warning "sections without a label are not considered landmarks"
Toggling the formatted version of the raw JSON
an expanded dropdown listing all the collapsible keys in the JSON file
a JSON file filtered down with the string 'slug', showing a list of slugs.
A snippet of a formatted JSON showing differnet styles for urls, fields, strings and dates. The dates have the date in readable text as comments.
Polypane showing a GitHub API response
Innovation in Business Tech Innovator Awards Best Accessibility Tool 2024 (Western Europe) Polypane
Crozdesk Quality choice: Top ranked solution 2024 Crozdesk Trusted vendor: High market presence 2024 Polypane