Mac storage basics · Browsers and everyday apps
Does macOS keep old versions of my documents, and do they use space?
Short answer: Yes — apps with Auto Save keep earlier versions (File → Revert To → Browse All Versions). macOS manages and thins them itself, so they rarely use much space.
Yes. Apps that use Auto Save — Pages, Numbers, Keynote, TextEdit, Preview and many others — keep earlier versions as you work. You can see them via File → Revert To → Browse All Versions.
macOS manages this store itself in a protected place on the disk and thins older versions over time, so it rarely grows large and there's no supported way to clear it by hand. If one document with heavy media has many versions, duplicating it (File → Duplicate) and deleting the old copy starts it fresh.