The Lighthouse Wordpress stack pack recommends serving images in nextgen formats. This means you need to upgrade to Webp or Avif. Webps images load faster than png or jpegs.
To create Webp images for newly uploaded jpegs, use the Wordpress performance team plugin Performance Lab, which will later be merged into Wordpress.
To transform png or jpegs to webp use the Converter for Media plugin and check all available images for conversion. It also has WP Cli support which enables faster image conversion from the server level.
Wordpress Avif
The AVIF format is still not popular but as more WordPress plugins add support, you should consider it. To upload AVIF images on WordPress, edit functions.php to add support.
The Converter for Media Pro plugin also offers Avif support.
Use Imagify, Smush, Optimole, or Shortpixel to have more image optimization features. Cloudflare also offers image optimization features, but may not offer the same compatibility and easiness to use as native Wordpress plugins.
Smush vs Imagify vs Optimole: Price and feature comparison
All plugins offer support for WEBp format, with Imagify and Optimole offering WebP conversion for free. Smush offers WebP conversion only on Pro plans.
As the popularity of the AVIF image format grows, so does the browser support, but Imagify does not support it yet. You can track when it will be added following this GitHub issue. Smush also doesn’t support AVIF, track its development here. Optimole also lacks support for AVIF.
Considering the current numbers, 1-year pricing on each product would be as follows:
- Imagify unlimited traffic: $100
- Imagify 500MB max/mo traffic limit: $50
- Smush 10GB max/mo traffic limit: $60
- Optimole 25,000 visits/mo limit: $240
| Functionality | Imagify | Smush | Optimole |
|---|---|---|---|
| .WEBp support | ✔️(Free Conversion) | (Pro plans) | ✔️(Free) |
| Image Optimization | ✔️(Free & Unlimited) | – | ✔️(Free & Unlimited) |
| Optimize images(size) up to | 32GB | – | (Auto-Scaled Images) |
| .AVIF support | ❌ | ❌ | ❌ |
Imagify
Imagify is a plugin from Wp Media, the creators of the Wp Rocket plugin, a leader in the caching plugin. It had more than 6 million downloads.
Optimole
Optimole is a plugin that currently offers up to 5,000 Visits/monthly on their free plan with CDN image optimization service. Optimole had more than 1 million downloads.
Smush
Smush is a popular image optimization plugin and offers many free features. It had more than 30 million downloads from the Wordpress plugin repository.