How often should I check my Mac’s health?

Glance at storage and battery every month or two. Run Disk Utility First Aid or Apple Diagnostics when something is wrong, not as routine.

Why is my Mac slow if its health looks fine?

Usually one app using a lot of processor or memory (check Activity Monitor), or a nearly full startup disk. A restart clears many temporary slowdowns.

Does checking battery health need an app?

No. System Settings › Battery shows Battery Health on Mac laptops. Apps can show more detail, such as charge cycles.

Mac file guides

How to check your Mac’s health

By Vishva Variya · Updated November 3, 2026 · 5 min read

Short answer

Check five things. Battery: System Settings › Battery › Battery Health should say Normal. Storage: System Settings › General › Storage, ideally with 10–15% free. Memory and processor: Activity Monitor’s Memory and CPU tabs. Disk: Disk Utility › First Aid. Hardware: Apple Diagnostics, from the power button on Apple silicon (then ⌘D) or D at startup on Intel.

How do I check my MacBook’s battery health?

1Choose Apple menu › System Settings, then click Battery in the sidebar.
2Look at Battery Health: Normal means it’s working as expected.
3Service Recommended means it holds less charge than when new, or isn’t working normally. The Mac is safe to use; consider a replacement if the runtime bothers you.

Click the ⓘ next to the condition for battery health management settings.

How do I check storage space?

1Open System Settings › General › Storage.
2Read the bar: how much is used, and by what.
3Click the ⓘ next to a category to see and remove its largest items.

macOS needs free space for updates, swap and caches; a nearly full disk is the most common reason a healthy Mac feels slow. If System Data is huge, see why System Data is so large.

How do I check memory and processor load?

1Open Activity Monitor (Applications › Utilities, or ⌘Space and type it).
2In the Memory tab, look at the Memory Pressure graph at the bottom: it shows how well memory is keeping up. A graph that stays high means apps are competing for memory.
3In the CPU tab, sort by % CPU to see which app is keeping the processor busy.

How do I check the disk for errors?

1Back up first.
2Open Disk Utility (Applications › Utilities).
3Choose View › Show All Devices, select a volume and click First Aid, then Run.
4Repeat for the container and then the device itself.

To repair the startup disk fully, run First Aid from macOS Recovery. If Disk Utility says the disk is about to fail, back up and replace it.

How do I run Apple Diagnostics?

1Apple silicon: shut down, then press and hold the power button until startup options appear. Release, then press ⌘D.
2Intel: restart and hold D as the Mac starts.
3Follow the prompts; the results list any hardware component that may be at fault, with a reference code.

Checking your Mac’s health with Peekaboo

Peekaboo’s Mac Health puts processor, memory, startup disk, network, heat and battery in one view and scores them from 0 to 100, with a sentence for every lost point and a button to the fix. When the disk is what costs points, Clean Up, Duplicates and Space Map are in the same app. It doesn’t replace Disk Utility or Apple Diagnostics for hardware faults. To compare dedicated monitors, see the best system monitor apps for Mac.

1Open Mac Health.⌥⇧⌘H
2Read the score and the reasons it isn’t 100.
3Click the button beside a reason to go straight to the fix.

Questions

How often should I check my Mac’s health?: Glance at storage and battery every month or two. Run Disk Utility First Aid or Apple Diagnostics when something is wrong, not as routine.
Why is my Mac slow if its health looks fine?: Usually one app using a lot of processor or memory (check Activity Monitor), or a nearly full startup disk. A restart clears many temporary slowdowns.
Does checking battery health need an app?: No. System Settings › Battery shows Battery Health on Mac laptops. Apps can show more detail, such as charge cycles.