Title: WebP WASM
Author: gecko43
Published: <strong>June 19, 2020</strong>
Last modified: June 19, 2020

---

Search plugins

![](https://ps.w.org/webp-wasm/assets/banner-772x250.png?rev=2327719)

This plugin **hasn’t been tested with the latest 3 major releases of WordPress**.
It may no longer be maintained or supported and may have compatibility issues when
used with more recent versions of WordPress.

![](https://ps.w.org/webp-wasm/assets/icon-256x256.png?rev=2327719)

# WebP WASM

 By [gecko43](https://profiles.wordpress.org/gecko43/)

[Download](https://downloads.wordpress.org/plugin/webp-wasm.zip)

 * [Details](https://wol.wordpress.org/plugins/webp-wasm/#description)
 * [Reviews](https://wol.wordpress.org/plugins/webp-wasm/#reviews)
 * [Development](https://wol.wordpress.org/plugins/webp-wasm/#developers)

 [Support](https://wordpress.org/support/plugin/webp-wasm/)

## Description

Convert jpeg and png images to their webp equivalents by leveraging google’s libwebp
and web assembly and serve webp images directly when supported in posts and pages.

### Quick start

 * Sign into the backoffice as an admin user.
 * Install the plugin and activate it.

### Convert a single media library image

 * Navigate to **Media > Library**
 * Select the **list view** icon
 * Locate a jpeg or png image for editing and click the media’s title link or the“
   edit” link under the entry.
 * Scroll down to the bottom of the edit page to the (new) _WebP Conversion_ section
 * Click **Create** to create a webp version of this media library image on the 
   server
 * Click **Delete** to delete a webp version if it exists for this media library
   image

### Convert all media library images

 * Navigate to **Plugins**
 * Set the quality and overwrite flag as desired
 * Click **Create** to create webp files for all media library images
 * Click **Delete** to delete existing webp files for all media library images

### How it works

The client (browser) creates a webp version of the image when the **Create** button
is clicked. This is then sent to the server where it is saved in the same folder
as the original image, but with a `.webp` extension.

For example, if the original image is

    ```
    /wp-content/uploads/2020/05/test.jpg
    ```

an additional

    ```
    /wp-content/uploads/2020/05/test.webp
    ```

will be created there.

A filter is applied in the WordPress hook `the_content` to swap an image for its
webp equivalent if available.

### More about the conversion

Conversion is done on the client, so a modern browser with wasm support is needed.
This is because conversion to webp with php requires shell_exec to make calls to
Google’s cwebp or other php extensions are needed. These features often pose security
risks that outweigh the benefits. This plugin gets around that by delegating the
actual image conversion to the client. It’s based on [this encoder](https://github.com/wrburnham/webp-wasm)
to save webp versions of uploaded jpeg and png images.

### License

This plugin is licensed as GPLv3.

### Notes

The simple html dom parser library is used to render webp images directly in WordPress
content where possible. The client-side conversion to WebP leverages Google’s libwebp.

## Screenshots

 * [[
 * Access the admin panel from the **Tools** menu.
 * [[
 * The admin panel for global (site-wide) conversion of images to WebP. A similar
   panel is available for individual media library images; to access this for an
   individual media resource, use the **Edit** link for the specific **Media** >**
   Library** resource.

## Reviews

There are no reviews for this plugin.

## Contributors & Developers

“WebP WASM” is open source software. The following people have contributed to this
plugin.

Contributors

 *   [ gecko43 ](https://profiles.wordpress.org/gecko43/)

[Translate “WebP WASM” into your language.](https://translate.wordpress.org/projects/wp-plugins/webp-wasm)

### Interested in development?

[Browse the code](https://plugins.trac.wordpress.org/browser/webp-wasm/), check 
out the [SVN repository](https://plugins.svn.wordpress.org/webp-wasm/), or subscribe
to the [development log](https://plugins.trac.wordpress.org/log/webp-wasm/) by [RSS](https://plugins.trac.wordpress.org/log/webp-wasm/?limit=100&mode=stop_on_copy&format=rss).

## Changelog

First release

## Meta

 *  Version **1.0**
 *  Last updated **6 years ago**
 *  Active installations **10+**
 *  Tested up to **5.4.19**
 *  Language
 * [English (US)](https://wordpress.org/plugins/webp-wasm/)
 * Tags
 * [image](https://wol.wordpress.org/plugins/tags/image/)[webp](https://wol.wordpress.org/plugins/tags/webp/)
 *  [Advanced View](https://wol.wordpress.org/plugins/webp-wasm/advanced/)

## Ratings

No reviews have been submitted yet.

[Your review](https://wordpress.org/support/plugin/webp-wasm/reviews/#new-post)

[See all reviews](https://wordpress.org/support/plugin/webp-wasm/reviews/)

## Contributors

 *   [ gecko43 ](https://profiles.wordpress.org/gecko43/)

## Support

Got something to say? Need help?

 [View support forum](https://wordpress.org/support/plugin/webp-wasm/)