RAMKeeper

RAMKeeper is a macOS menu bar app that shows which app is using your memory. Instead of a single system-wide percentage, it breaks memory down per app and per browser renderer process, with current and peak values, so you can see which tab or app keeps growing.

The free direct download shows this attribution. A one-time $19 Pro unlock adds threshold rules (for example, notify or suspend an app that stays above 6 GB for five minutes; off by default), Focus Mode to suspend background apps in one click, and gentle restarts of the worst offender.

No subscription, no ads, no tracking. Universal app for macOS 12 or later, Developer ID signed and notarized. A free sandboxed version is also on the Mac App Store.