The Mac Health score, explained: every number, every threshold

A health score is an easy thing to fake and a hard thing to make honest. The temptation is a big green number that reassures everyone, with a few scary ones to sell an upgrade. SweepyMac's Mac Health score is built the opposite way: every input is something you can check yourself, every threshold is published, and a check that cannot read its data is left out rather than counted as a pass. Here is the whole thing.

The score and its bands

The ring shows a number from 0 to 100 and a rating. 85 and above is Excellent. 70 to 84 is Good. 50 to 69 is Fair. Below 50 is Needs attention. Underneath, either "No issues found" or "N items need your attention", plus your uptime and macOS version.

Four things feed the score: storage, memory, battery and startup load. Each has a tile under the ring showing its current value, and the tiles are read directly from macOS. Storage is the percentage of the boot volume used. Memory is the share of RAM in use. Battery is maximum capacity, or charge level if capacity is not available, and "No battery" on a desktop Mac, which then drops out of the calculation. Startup is the number of login items in your account.

Every recommendation, and when it fires

The recommendations are where the score becomes actionable. Each one is a sentence with a button that jumps to the module that fixes it, or a dismiss. These are the triggers, exactly as the app applies them.

Recommendation	Fires when	Button goes to
Disk almost full (critical)	90% or more used, or under 8 GB free	Cleanup
Disk filling up	80% or more used	Cleanup
Memory under pressure	90% or more of RAM in use	Performance
Battery worn out (critical)	Maximum capacity under 70%	Battery
Battery wearing down	Capacity under 80%, or macOS reports Service Recommended	Battery
Lots of startup items	More than 8 login items	Performance
Several startup items (info)	More than 4 login items	Performance
Time to restart	Up for 14 days or more	Dismiss
Consider a restart (info)	Up for 7 days or more	None

The two marked critical are the ones that hurt the score most, and for good reason. A boot volume with under 8 GB free is the point where macOS itself starts struggling: swap has nowhere to go, updates fail to download, and apps that write temporary files begin to misbehave. A battery under 70 percent of its original capacity is one Apple's own diagnostics would flag for service.

What is deliberately not in it

Nothing about junk files. A Mac with 20 GB of caches and a half-empty disk is a healthy Mac; the caches are a Cleanup question, not a health one. Nothing about malware either, because a signature scan is a yes-or-no answer that should never be averaged into a number. And nothing subjective: no "optimisation level", no "performance index". If a value is not something macOS reports, it is not in the score.

Skipped, not passed

This is the rule we care most about. If a check cannot read its data, it is skipped. The disk check that gets a permission error does not report a clean disk; it reports nothing, and the score is computed from the checks that did run. A Mac with no battery is not marked as having a perfect battery. The alternative, treating "could not read" as "fine", is how a health score ends up lying with a straight face.

The same rule runs through the rest of the app. Scans that could not read a folder show an orange triangle. Space Lens labels what it could not measure. We wrote about why in what a Mac cleaner should never do.

Where else it shows up

The score also appears on Smart Scan, in the "Your Mac at a glance" tiles under the scan results, and the recommendations appear there as cards. Tapping one jumps to the fix. If everything is fine you get "You're all caught up", and the Health tile just reads the score and its rating.

Re-check at the top of Mac Health re-runs everything and brings back any recommendation you dismissed. Dismissing is for cards you have read and chosen to ignore, such as a restart reminder on a Mac that is deliberately up for a month; it does not change the score, only what is shown.

Reading a bad score

Start with the critical items, because one of them is usually the whole story. In the screenshot on the SweepyMac page, a score of 53 comes from a disk at 3 GB free and a battery at 75 percent capacity with Service Recommended. Free the disk and the score climbs into Good on its own; the battery is a hardware fact that only a replacement changes, and the app says so rather than offering to fix it with software.