Guides
Which Mac app to use for which job, and what Activity Monitor's figures mean. Every price and feature comes from the maker's own site.
Fix a problem
What is wrong and how to find the cause, with the Mac's own tools first.
- Why is my Mac so slow Mac running slow? Find the cause in Activity Monitor: an app at high CPU, memory pressure, a full disk, heat or indexing, and the fix for each. 6 steps
- What’s draining my Mac’s battery Mac battery draining fast? Find the app behind it with Activity Monitor’s Energy tab and the battery menu, check battery health, and fix the usual causes. 6 steps
- Which app is using my CPU or memory Check CPU and memory usage on a Mac, per app: Activity Monitor step by step, why % CPU passes 100%, and when high memory use is actually a problem. 6 steps
- Why won’t my Mac sleep Mac won’t sleep? Find the app keeping it awake with one Terminal command or Activity Monitor, see why it wakes at night, and fix the settings behind it. 5 steps
- Chrome using too much memory Chrome using too much memory on your Mac? Find the tab or extension behind it with Chrome’s Task Manager, see when it matters, and what lowers it. 5 steps
- Why are my Mac’s fans so loud Mac fan loud? Find the app heating your Mac in Activity Monitor, check airflow and temperatures, and learn when a loud fan is normal and when it is not. 5 steps
- How to control fan speed on a Mac macOS has no fan speed setting. What Energy Mode changes, how to set a Mac’s fan speed with an app, and when a faster fan helps. 4 steps
- How to free up RAM on a Mac How to free up RAM on a Mac: find the app holding memory, what actually frees it, why memory cleaners don’t help, and when full memory is fine. 6 steps
- Docker using too much memory Docker using too much memory on your Mac? See which container is using it, cap the Docker VM’s memory, and get memory back when containers stop. 5 steps
- How to stop Docker containers Stop one Docker container or all of them on a Mac: docker stop, compose stop and down, stop versus kill, and why a container starts again. 5 steps
- Volume mixer for Mac macOS has no volume mixer. How to turn down one app on a Mac with the controls you have, and how to get a volume slider for every app. 5 steps
Best apps, ranked
Each app is labeled with the job it does best, with its pros and cons. Prices checked September 22, 2026.
- The 12 best Activity Monitor alternatives for Mac The best Activity Monitor alternatives for Mac, compared: Vitals, iStat Menus, Stats, btop and more, with prices, pros and cons checked in 2026. 12 apps
- The 9 best iStat Menus alternatives for Mac The best iStat Menus alternatives for Mac in 2026: Stats if you want it free, Vitals if you want to know which app is behind the figure, and seven more, with prices checked. 9 apps
- The 9 best Stats alternatives for Mac The best Stats alternatives for Mac in 2026: Vitals if you want to know which app is behind the figure, iStat Menus for the most in the menu bar, and seven more, with prices checked. 9 apps
- Task Manager for Mac: the built‑in one, and the 7 best apps The Mac's Task Manager is Activity Monitor. How to open it, how to force quit an app, and the 7 best Task Manager apps for Mac, with prices checked. 7 apps
- The 10 best system monitors for Mac The best system monitor apps for Mac in 2026: Vitals, iStat Menus, Stats, MacPulse and more, ranked on which app is behind the figure, with prices checked. 10 apps
- The 8 best menu bar system monitors for Mac The best menu bar system monitors for Mac in 2026: Vitals, iStat Menus, Stats and more, compared on what each puts in the menu bar, with prices checked. 8 apps
- The 7 best volume mixers for Mac The best volume mixer apps for Mac in 2026: SoundSource, SoundDial, Vitals, FineTune and more, compared on per-app volume, routing and price. 7 apps
Vitals compared
Vitals set against each app, row by row, and when the other one is the better pick.
- Vitals vs Activity Monitor Activity Monitor: the process monitor that comes with macOS.
- Vitals vs iStat Menus iStat Menus: a menu bar monitor.
- Vitals vs Stats Stats: a free, open-source menu bar monitor.
- Vitals vs MacPulse MacPulse: a system monitor that explains performance in plain English.
- Vitals vs iStatistica Pro iStatistica Pro: a system monitor with widgets and a web dashboard.
- Vitals vs ProcXray ProcXray: a process explorer for developers.
- Vitals vs Sensei Sensei: a Mac performance monitor and cleaner.
- Vitals vs CleanMyMac Menu CleanMyMac Menu: the menu bar part of CleanMyMac.
- Vitals vs TK-mac TK-mac: a Task Manager in the Windows style.
- Vitals vs ProcessSpy ProcessSpy: a process explorer, in the mould of Windows Process Explorer.
- Vitals vs SoundSource SoundSource: sound control for the Mac: per-app volume, routing and effects.
- Vitals vs SoundDial SoundDial: a per-app volume mixer for the menu bar.
- Vitals vs eqMac eqMac: a system-wide equalizer, with a per-app mixer in Pro.
Activity Monitor glossary
55 terms: the processes near the top of the list, what each figure means, and what to do when something goes wrong.
Open the glossary From kernel_task and WindowServer to memory pressure and Energy Impact.Jump to processes you will see, memory, CPU, GPU and energy, when something goes wrong or figures Activity Monitor leaves out.