logo

Autoprefixer: You might be using it without even knowing!

Learn more about autoprefixer, what is the use for it and do you actually use it or not.
3/2/2025

Cross-browser Compatibility

Before diving into Autoprefixer, let's talk about cross-browser compatibility. It ensures your web application works consistently across various browsers and devices.

Browser Differences

Different browsers (Chrome, Firefox, Safari, Edge, etc.) and their versions can interpret HTML, CSS, and JavaScript differently. This is because not all browsers support the latest web standards or features.

Vendor Prefixes

You've probably seen things like -webkit-, -moz-, or -ms- in your CSS files or browser dev tools. These are "vendor prefixes," used to target specific browsers and apply styles accordingly.

Autoprefixer Explained

Autoprefixer is a PostCSS plugin that parses your CSS and automatically adds vendor prefixes. It uses data from Can I Use to determine which prefixes are needed based on browser compatibility. It adds prefixes according to the browser that is opening the session.

Example

Consider this CSS:

::placeholder {
  color: gray;
}

In Firefox, Autoprefixer might transform it to:

::-moz-placeholder {
  color: gray;
}
::placeholder {
  color: gray;
}

Do You Need to Install Autoprefixer?

It depends on your tech stack.

Included

  • Next.js, Vite, and React (created with create-react-app or create-vite-app) typically include Autoprefixer in their CSS processing pipelines.

May need to install

  • Older Tailwind versions.

No need to install

  • Tailwind CSS v4.0 utilizes Lightning CSS for vendor prefixing.

Component Libraries

  • If you're building a component library for diverse projects, including Autoprefixer in your build process is a good idea.