WordPress Caching Explained: Page Cache, Browser Cache and CDN

Caching makes WordPress faster by avoiding repeated work. The confusing part is that several different systems are called a cache. Each stores something different and solves a different delay.

Page caching

WordPress normally runs PHP and database queries before returning a page. A page cache stores the completed HTML so later visitors can receive it without repeating the full process.

This is usually the most important caching layer for a brochure site or content site. Logged-in users, baskets and personalised pages may need exclusions.

Browser caching

Browser caching tells a visitor’s browser how long it can reuse images, fonts, CSS and JavaScript. A returning visitor then avoids downloading unchanged files again.

Object caching

Object caching stores the result of repeated database work. It can help busy or database-heavy sites, but it is not a replacement for full-page caching.

CDN caching

A content delivery network keeps copies of static files in multiple locations. Visitors can download them from a location nearer to them. Some CDNs can also cache complete pages.

Why more caching plugins are not better

Two plugins trying to minify the same files or control the same page cache can conflict. Choose one clear owner for each job and document the setup.

A safe caching checklist

1. Take a current backup.
2. Enable one page-cache system.
3. Exclude checkout, account and personalised pages.
4. Test logged-out and logged-in journeys.
5. Purge the cache after important changes.
6. Measure representative pages before and after.

Continue with the interactive WordPress speed audit.