Baseline
Web Platform Baseline brings clarity to information about browser support for web platform features.
Baseline gives you clear information about which web platform features are ready to use in your projects today. When reading an article, or choosing a library for your project, if the features used are all part of Baseline, you can trust the level of browser compatibility.
Who defines Baseline?
Baseline was originated by the Chrome team and is now defined by the WebDX Community Group.
How do things become Baseline?
Baseline has two stages:
- Newly available: The feature is supported by all of the core browsers, and is therefore interoperable.
- Widely available: 30 months have passed since the newly interoperable date. The feature can be used by most sites without worrying about support.
Prior to being Newly available, a feature has Limited availability when it's not yet supported across browsers.
The core browser set
- Chrome (desktop and Android)
- Edge
- Firefox (desktop and Android)
- Safari (macOS and iOS)
Baseline at I/O
What's new in web
Google I/O is here, and there's a bunch of news to share about Baseline and what's new to the web at large. Learn more in this post.
Baseline and tooling
As Baseline has matured, we've seen that more developers are beginning to integrate it into their development workflows. Learn about the latest tools to integrate Baseline, as well as resources you can use to build your own tools!
Browserslist now supports Baseline
Browserslist has added support for Baseline queries. Find out what that could mean for your developer workflow.
Create Baseline tools with the web-features package
Learn how to use the data in the web-features npm package to create your own Baseline tools!
The Baseline Tooling Hackathon starts now!
Want to make the web better for a chance to win cash prizes? Join the Baseline Tooling Hackathon!
Baseline for CSS properties now in Chrome DevTools
Baseline information is now available for CSS properties in the Elements panel of Chrome DevTools!
How to use Baseline in your project
Learn how to integrate Baseline into your project with this codelab.
WebStatus.dev: Now with more data, deeper insights, and a clearer path to Baseline
Announcing improvements to the Web Platform Dashboard.
The Baseline Netlify extension has shipped
The Baseline Netlify extension helps developers to understand which Baseline targets are best supported by users. Learn more in this post on how to use it!
Visual Studio Code now supports Baseline
Learn about the new Baseline support in VS Code.
Use Baseline with Browserslist
Add Baseline to your development linting and packaging tools with Baseline-specific queries now built into Browserslist.
How to query the Web Platform Dashboard for Baseline tooling
Learn about the Web Platform Dashboard and how you can query its HTTP API to help you build Baseline tools.
Support for CSS and Baseline has shipped in ESLint
You can now use ESLint to lint CSS and enforce usage of Baseline CSS features in your project! Learn more in this blog post.
Baseline theory
Adopting Baseline in your projects means there are some considerations you need to make. These materials will help you to answer the hard questions, from polyfilling, tooling, and more.
How to choose your Baseline target
Learn what Baseline targets are, how to choose one, and how it can help your development experience.
How to think about Baseline and polyfills
Knowing when to reach for a polyfill can be a hard decision, but using Baseline features can help you answer this question. Learn more in this guide!
Case studies
Read these case studies to learn how developers in the industry are adopting Baseline as a part of their work to simplify browser support criteria and adoption of interoperable web features.
How Target.com used Baseline to modernize features
Learn how Target adopted Baseline, and how it changed their awareness and adoption of interoperable web features.
How Cybozu eliminated browser compatibility overhead with Baseline
Read about how Cybozu, a groupware company in Japan, adopted Baseline to simplify their browser support criteria.
Making Baseline actionable with real user data
How RUMvision incorporated Baseline information with their RUM data.
The Baseline monthly digest
The Baseline monthly digest is a monthly newsletter that highlights what happened each month with Baseline, including new features, community updates, and anything else that fits!
Baseline targets
When features become part of Baseline in a given year, they're grouped into a feature set—also known as Baseline targets. Here are just a few of the targets you can explore to see what features you can use today.
Baseline 2025
There are still many browser releases to come in 2025, and as they arrive, they will be part of Baseline 2025. Follow along as we announce new features throughout the year.
Baseline 2024
All items that become part of Baseline Newly available in 2024 can be referred to as Baseline 2024. We published a post at the end of 2024 to round up all the features that landed during the year.
Baseline 2023
All items that become part of Baseline Newly available in 2023 can be referred to as Baseline 2023. We published a post at the end of 2023 to round up all the features that landed during the year.
Size container queries
Size container queries became Baseline Newly available in February 2023.
:has()
:has() became Baseline Newly available in December 2023.
Subgrid
Subgrid became Baseline Newly available in September 2023.
CSS Nesting
Nesting became Baseline Newly available in August 2023.
HTML <search> element
The
<search> element became Baseline Newly available in October 2023.
Responsive video
Responsive video became Baseline Newly available in November 2023.
The inert attribute
The
inert attribute became Baseline Newly available in April 2023.
Constraint Validation API
The Constraint Validation API became Baseline Newly available in March 2023.
:user-valid and :user-invalid
:user-valid and :user-invalid became Baseline Newly available in October 2023.
Compression Streams
Compression Streams became Baseline Newly available in May 2023.
Declarative Shadow DOM
The Declarative Shadow DOM became Baseline Newly available in February 2024.
Popover
Popover became Baseline Newly available in January 2025.