WebP and Open Source: Licensing and the Project

WebP is open source and royalty-free, which is a large part of why it spread across the web where patent-encumbered formats stalled. Its reference implementation, libwebp, is published under a permissive BSD licence with an additional patent grant. This guide covers the licensing, the project, and what it means for using WebP commercially.

For the format itself, see What is WebP?. For installing and using the library, see libwebp: Installation, Tools, and the C API.

Is WebP open source?

WebP is open source. Its reference implementation, libwebp, is developed by Google in the open as part of the WebM project and published with full source code. Anyone can read, build, modify, and redistribute it. The format specification is also public, now formalised as RFC 9649.

Open development is why WebP support could be added to browsers, editors, and libraries across the industry without licensing barriers.

What licence does libwebp use?

libwebp is released under a 3-clause BSD licence, a permissive open-source licence. It allows use, modification, and redistribution in both open-source and proprietary software, provided the copyright notice is retained. There are no copyleft obligations.

The permissive licence means libwebp can be embedded in commercial applications without releasing your own source code.

Is WebP royalty-free?

WebP is royalty-free. Google provides an additional patent grant — documented in the project's PATENTS file — covering the techniques the format uses. This removes the patent-licensing cost that burdens some codecs and was a deliberate design goal.

Royalty-free status is a key contrast with formats like HEIC, whose HEVC codec carries patent licensing. See WebP vs HEIC.

Where is the WebP source code?

The libwebp source lives in Google's WebM repository, hosted at chromium.googlesource.com/webm/libwebp, with a mirror on GitHub. It contains the encoder and decoder libraries plus the command-line tools — cwebp, dwebp, gif2webp, webpmux, and others. Releases are tagged and documented there.

The tools built from this repository are covered in cwebp Command-Line Tool and dwebp: How to Decode and Preview WebP Files.

What does this mean for commercial use?

You can use WebP freely in commercial products, websites, and services with no licence fee or royalty. The BSD licence and patent grant together make it safe to encode, decode, serve, and embed WebP at any scale. This legal simplicity is a practical reason to prefer it over patent-encumbered alternatives.

For most teams the licensing is a non-issue precisely because it is so permissive — which is the point.

Where to go from here

WebP is open source under a permissive BSD licence and royalty-free through Google's patent grant. That legal openness, as much as its compression, is why WebP became the web's default modern image format.