What it is
The cache keeps a ready copy of each page and serves it to the next visitors, without redoing WordPress's work on every visit. Logged-in users always see the live version.
How to use it
- Turn it on with the Recommended profile in the wizard, or in the Modules screen.
- The cache clears itself when you publish or edit a page, post or product.
- To clear everything manually, use the "Clear cached pages" button in the Speed screen.
Common problems
I changed the page and visitors still see the old one.
Use "Clear cached pages" in the Speed screen. If your server or a service such as Cloudflare also keeps a copy, clear it there too.
The plugin says another cache already exists.
Hosts such as Kinsta, WP Engine and SiteGround, or another cache plugin, already handle this. Ranking Suite keeps its own cache off so they don't clash.
If something goes wrong
Turn off the Cache module under Modules. The plugin removes the cache files and the rule it created.
Didn't find the answer? Ask in the WordPress.org support forum.