WebP + AVIF converter

Fast, simple & free plugin to automatically convert and serve WebP & AVIF images.

Features

• Automatically convert and serve WebP/AVIF images.
• Increase your Google Pagespeed.
• Only images which are really used will be converted, does not convert the whole media library.
• WebP/AVIF quality is adjustable (default 100% = no quality loss)
• No image URLs are changed, solution is purely based on .htaccess rewrite rules.
• Serve original format in case the browser does not support WebP/AVIF (relying on the “Accept” header).
• The following source formats are supported: JP(E)G, PNG, GIF, BMP.
• Extra feature: WebP images are served as PNG when the browser/client does not support WebP (e.g. Microsoft Outlook).

Browser support

• WebP: all modern browsers
• AVIF: Chrome, Firefox, Safari (Edge doesn’t support AVIF yet)

Good to know

• It may take a few minutes before the WebP/AVIF images are generated after activating the plugin.
• AVIF is a relatively new format, and not widely supported yet on servers. This depends on your server configuration (see Server requirements).
• Generating AVIF images is CPU-intensive, and may take a while.
• WebP/AVIF format is only served when this format is smaller than the original file. Depending on the image, WebP/AVIF is not always the most efficient format.
• Animated GIF-images are not supported yet as GDlib/ImageMagick don’t have support for it

How the plugin works

The plugin does nothing until the first image is requested. Here is the conversion flow.

1. Original image is requested in browser
2. Image is added to the conversion queue, original image is still served.
3. Conversion queue is processed in background, queued images are converted to WebP/AVIF format.
4. When the image is requested now, and the browser supports WebP and/or AVIF, the WebP/AVIF image is served.

Server requirements

• Apache 2.x with mod_rewrite or Nginx
• ImageMagick or GDlib with WebP support
• ImageMagick or GDlib with AVIF support (optional)
  • You can use this plugin without AVIF support, in that case only WebP conversion is done

Installation (Apache)

The .htaccess rules are applied automatically when activating the plugin. Install the plugin and go!

Installation (Nginx)

You have to add the following lines to your nginx configuration:
In the http section (outside the server section):

map $http_accept $webp {
    default ".nonexisting";
    "~*image/webp" ".webp";
}

map $http_accept $png {
    default ".png";
    "~*image/webp" "";
}

map $http_accept $avif {
    default ".nonexisting";
    "~*image/avif" ".avif";
}

In the server section, above the “location /” rule:
(Change the wp-content part if this folder is in a non-standard location.)

location ~* wp\-content/(?!cache/fastware\-webpavif).+\.(jpe?g|png|gif|bmp|webp)$ {
    if (!-f $request_filename) {
        break;
    }
    rewrite /wp\-content/(.+)$ /wp-content/cache/fastware-webpavif/$1;
}

location ~* cache/fastware\-webpavif.+\.(jpe?g|png|gif|bmp)$ {
    add_header Vary Accept;
    expires 30d;
    try_files $uri.pref$webp $uri.pref$avif $uri$webp $uri$avif $uri /?fw-webp-avif-ondemand=all;
}

location ~* cache/fastware\-webpavif.+\.webp$ {
    add_header Vary Accept;
    expires 30d;
    try_files $uri$png /?fw-webp-avif-ondemand=png;
}

If there exist a rule for images like location ~* ^.+.(ogg|…|jpg|jpeg|gif|png|webp|ico|bmp|…)$:

Please remove the following matching extensions: jpg|jpeg|gif|bmp|webp|avif.

In the mime.types file, make sure the following lines are present:

image/webp                                       webp;
image/avif                                       avif;

1. 

   Settings page

2. 

   PageSpeed Insights

Releases

• 2.0.7 [03-07-2023] Fixed redirect loop
• 2.0.6 [13-05-2023] Fixed issue with background converts
• 2.0.5 [06-05-2023] Added support for GDlib AVIF conversion (PHP >= 8.1)
• 2.0.4 [06-05-2023] Fixed error in loopback test on plugin configuration page
• 2.0.3 [06-05-2023] Fixed error in loopback test on plugin configuration page
• 2.0.2 [02-05-2023] More detailed checks/errors on plugin configuration page
• 2.0.1 [25-04-2023] Fix in wrong .htaccess rule
• 2.0.0 [25-04-2023] Added support for nginx
• 1.1.4 [07-04-2023] Fixed issue with rewriterules test
• 1.1.3 [07-04-2023] Show statistics of converted/queued/skipped images
• 1.1.2 [29-03-2023] Added support for converting GIF images
• 1.1.1 [28-03-2023] Added support for converting BMP images
• 1.1.0 [20-03-2023] Added WebP/AVIF quality settings
• 1.0.8 [15-03-2023] .htaccess fix + minor change in plugin name
• 1.0.7 [13-03-2023] Added admin dashboard to check plugin/server configuration
• 1.0.6 [07-03-2023] Fixed redirect bug on servers without avif support
• 1.0.5 [04-03-2023] Moved working directory, to improve cleanup after uninstall
• 1.0.4 [27-02-2023] Added support for PHP 7.4, fixed issue with scheduled converts
• 1.0.3 [22-02-2023] Adjust code to improve quality
• 1.0.2 [21-02-2023] Bugfix in GD convert
• 1.0.1 [18-02-2023] Stricter typing & ImageMagick as primary converter with GD as fallback
• 1.0.0 [17-02-2023] Initial version