Myth: 'RAM cleaner' and memory booster apps speed up your Mac — via Apple Support

MythmacOS 14 Sonoma and later

Memory booster apps show a scary 'used RAM' number and 'free' it with one click. But macOS deliberately fills spare RAM with cached files to make things faster. Throwing that cache away just means it has to be rebuilt, and the app itself uses memory and CPU in the background.

What to do instead

Uninstall memory cleaner apps and remove their login items (System Settings > General > Login Items).
Judge memory by the Memory Pressure graph in Activity Monitor. Only if it stays high is more RAM, or fewer open apps and tabs, the answer.

Apple explains that memory pressure is based on free memory, swap rate, wired memory and cached files together, and that cached files help performance.

Sources

View memory usage in Activity Monitor on Mac — by Apple Support
Q&A: Pointless purges — by Howard Oakley, The Eclectic Light Company

Source reviewed: 2026-11-02
Link checked: 2026-11-02
Tested hands-on: Not by Oddbyte.Me

Oddbyte.Me hasn't tried this on every macOS version, so keep the undo handy.

ram cleanermemory boosterfree memorymythspeed up mac

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