Frequently Asked Questions

1. What is WebP? Why should I use it?
2. I'm a webmaster. What do I need to know about web development before I can use WebP?
3. Why did Google release WebP as open source?
4. How can I convert my personal images files to WebP?
5. How can I judge WebP image quality for myself?
6. How do I get the source code?
7. What is the maximum size of a WebP image?
8. What color spaces does the WebP format support?

What is WebP? Why should I use it?

WebP is a method of lossy compression that can be used on photographic images. The degree of compression is adjustable so a user can choose the trade-off between file size and image quality. WebP typically achieves an average of 39% more compression than JPEG and JPEG 2000, without loss of image quality (see Comparative Study).

A WebP file consists of VP8 image data, and a container based on RIFF. Webmasters, web developers and browser developers can use the WebP format to create smaller, better looking images that can help make the web faster.

I'm a webmaster. What do I need to know about web development before I can use WebP?

Webmasters who are interested in improving site performance and who usually optimize the JPEG images on their site for quality can create WebP files easily. In order to use these files at serving time, they can target browsers that support WebP (as of April 2010, Google Chrome 9+ and Opera 11.10 beta).

Why did Google release WebP as open source?

We deeply believe in the importance of the open source model. With WebP in open source, anyone can work with the format and suggest improvements. With your input and suggestions, we believe that WebP will become even more useful as a graphic format over time.

How can I convert my personal images files to WebP?

You can use the WebP command line utility to convert your personal image files to WebP format. See Using WebP for more details.

How can I judge WebP image quality for myself?

Currently, you can view WebP files by converting them into a common format that uses lossless compression, such as PNG, and then view the PNG files in any browser or image viewer. To get a quick idea of WebP quality, see the Gallery on this site for side-by-side photo comparisons.

How do I get the source code?

The converter code is available on the downloads section of the WebP open-source project page. The code for the lightweight decoder and the V8 specification are on the WebM site. See the RIFF Container page for the container specification.

What is the maximum size a WebP image can be?

WebP is bitstream-compatible with VP8 and uses 14 bits for width and height. The maximum file size for WebP is 16383x16383 pixels. 

What color spaces does the WebP format support?

WebP uses the color spaces supported by the VP8 bitstream. Please refer to the first paragraph of "Chapter 2: Format Overview" in the VP8 bitstream specification.