WebP with WordPress

| | |

Controling your website’s image sizes has become a top priority among Web developers Here is the reason why:
As of  2017 end , HTTPArchive.org reports that images comprised 54% of the total page download size. And since response  time is inversely related to page load, developers wanting to achieve 2 seconds or better response time have to manage their image sizes. So  developers should be interested in in the improvements of the past year in the WebP image format. Webp  has achieved  both better compression of images  and some breakthrough acceptance on the Web. Our PhotoFinish blog describes the details of how Google-sponsored WebP has has achieved breakthrough browser support plus a better acceptance among content creation tools like photo editors and CMS-Content Management Systems. However, there was a notable exception among the CMS systems – WordPress. Surprise, WordPress has WebP support that might best be described as reluctant.

Here is what WordPress officially acknowledges as supported image formats.
WordPress.com – .gif, .jpg/.jpeg, .png
WordPress.org – gif,  ,ico, .jpg/.jpeg, .png
WordPress.org support – about a year and half ago there was a 17 reply discussion of implementing WebP in WordPress. A function for uploading .webo image formats was supplied but this still required thumbnail and display handling routines in the WP Core. Also support noted that  PHP GD and Imagick routines had to be fully enabled on hosting servers. These are some of the issues encountered when was we tested some of the current WordPress WebP plugins
List of WebP Plugins Tested
As seen in the 8 WebP plugin tests described below, the very same issues cited about PHP/GD/Imagick settings, WebP setup in WordPress were issues where DIY solution were required by hosting services, the plugins, and WordPress itself in WebP image format support

Flying Images – has a CDN, Lazy Loading and on the fly compression to WebP. But the WebP compression failed to work on websites hosted by BoldGrid and A2Hosting and only partially on Siteground website.
Images to Web – rejected by A2Hosting, and Siteground hosting for not having  the right  WebP PHP and  usage settings but worked in Boldgrid sometimes – standard imagesize were displayed on test page but not resized images which reverted to jpg.
Imagify – bulk compression existing media library images to WebP with backup and restore options, freemium service supports 25MB/month free conversion with 1GB/month for $4.99US to 50GB/month for $69.99US. Delivers 3 levels of compression: lossless, aggressive, ultra. Works with and may improve Kraken, Short Pixel, WP Smush , Optimus, EWWW compressions.  EXIF data is optionally retained or removed. However, in real world tests none of the images were  converted to Webp on Boldgrid and SiteGround websites.

Optimole-WP – like Flying Images has a CDN, lazy lending, upload and bulk image compression with conversion to WebP as an option Optimole offers freemium pricing start at 5000 free visits /month  where a unique visits is “anyone who visits your site once will be counted as a unique daily user. Each user is only counted once. It doesn’t matter what they do on your site, how many images they download, or how many pages they visit; it’s just one user. If they leave your site and return on the same day, they are still just one user.” But in our tests on SiteGround website showed no compression or conversion of images to webp
Plus Webp  – works in BoldGrid  with all bulk compressed and uploaded images diplayed in WebP for all sizes but unable scale or edit Webp images. Then on websites hosted by
ShortPixel  – has bulk optimization with control for EXIF data. But all images fail to convert on A2Hosting and BoldGrid systems. Also freemium conversion supports up to 100 images for free.
WebP Images – alters .htaccess, must be Apache server, will convert existing image files to WebP, will change image uploads to WebP. Problem occurred as  Webp upload images disappeared.
WebP Converter for Media – rejected by A2Hosting, Boldgrid, and Siteground hosting for not having  the right  WebP PHP and  usage settings

Even the SaaS image compression vendors had mixed success in uploading, editing and then delivering  WebP images. WebP support in WordPress is like WebP support in browsers a year or two ago – messy.


But Automattic and WordPress.org have a number of problems associated with WebP. First, there are over a dozen WordPress plugins that attempt to implement WebP but as we see above with mixed results. Even when they are able to upload or convert WebP file to the Media Library our tests were never able to edit or scale those images in the Media library like JPG files. Second, AVIF and JPEG  XL both have been shown to have better compression performance  than WebP [just follow the previous links].Third, Image Compression SaaS and CDNs are taking over image compression, scaling and management – will they replace the much maligned Media library? Finally,  HTTPArchives  shows that video page weight now eclipses image weight by a factor of 2 – so does this mean image compression decisions take second fiddle to video compression for WordPress. Stay tuned.

Similar Posts