How to Clear WordPress Cache

Multiple caches stack

A typical production site combines page HTML cache (plugin or reverse proxy), object cache for queries and fragments (Redis via drop-in or plugin), opcode cache (PHP OPcache), browser cache, and a CDN. Clearing only one layer leaves stale HTML or assets elsewhere—identify which layer served the outdated response using response headers and timestamps.

Practical order

Layer	How	Watch for
Object cache	`wp cache flush` (WP-CLI) or plugin button	WooCommerce sessions, cart fragments
Page cache	Plugin purge / Nginx helper	Mobile vs desktop variants
OPcache	php-fpm reload or opcache_reset in controlled context	Brief latency blip
CDN	Plugin webhook or dashboard purge	API rate limits

Transients and cron

Some “stuck” admin notices are transients in the database—use dedicated cleanup tools or WP-CLI transient delete --all cautiously. Do not confuse them with Redis object cache entries.

Frequently Asked Questions

Q.Does wp cache flush clear page cache plugins?

It flushes the WordPress object cache API layer; many page cache plugins still require their own purge button or hook—read your plugin docs.

Q.Why is the admin bar still wrong after deploy?

OPcache may still serve old PHP files; reload php-fpm or Apache mod_php workers, then purge page cache and CDN.

Q.Will clearing cache break WooCommerce carts?

Flushing object cache or sessions can—avoid broad Redis FLUSH during peak sales; use targeted key deletes or maintenance windows.

Q.How do I clear cache from WP-CLI?

Run wp cache flush for object cache; many plugins expose wp rocket clean or vendor-specific commands—install matching CLI packages.

Q.Why does only one page stay stale?

Often a CDN cache key on that URL, a stale transient, or a partial page cached with fragment caching—inspect response headers and plugin rules.

Q.Should I delete all transients regularly?

Not blindly—some transients back scheduled tasks or rate limits; prefer plugin-aware cleanup or targeted deletes.

Q.Does multisite need per-site purges?

Yes—network-activated plugins may still cache per blog ID; run purges in context of each site or use network-aware CLI flags.

Q.Is database optimization the same as cache clear?

No—optimizing tables rebuilds storage; it does not replace purging object/page caches or fixing bad Cache-Control headers.

Multiple caches stack

Layer

How

Watch for

Object cache

wp cache flush (WP-CLI) or plugin button

WooCommerce sessions, cart fragments

Page cache

Plugin purge / Nginx helper

Mobile vs desktop variants

OPcache

php-fpm reload or opcache_reset in controlled context

Brief latency blip

CDN

Plugin webhook or dashboard purge

API rate limits