Find what's
draining your Mac

Yes, as a separate edition: free to download, with Pro as a one-time purchase inside it, $9.99 in the US; the yearly $9.99 on this page is for the version sold here. The App Store sandbox does not let that edition close an app for you, count the helper processes an app started after they have quit, or read the sleep log that names what woke your Mac. It also has no once-a-second power reading and no separate screen backlight line, uses one fixed floor for every Mac instead of measuring yours, and does not measure graphics, so a window in front is not credited to its app. Those stay with the version sold here. The App Store edition has no network access at all: Apple's App Store handles its Pro purchase. The version here is notarized by Apple: the malware check Apple runs on apps distributed outside the App Store.

Activity Monitor ranks apps by Energy Impact, a score with no unit: it shows which app is heavier, not how many minutes quitting it gives back. WattMate shows each app in watts and the minutes you get back, then measures what quitting actually changed.

Sometimes. Telling the difference is the whole product. The usual answer online is "no, macOS handles it", and for most apps that is true. WattMate lists every app in watts but suggests quitting one only when it is worth real minutes, and a couple of minutes after you quit, it measures the Mac again and prints what actually changed, or says plainly that the effect could not be isolated. The check comes from your Mac, not from a rule of thumb.

Health and hours answer different questions. Health (capacity and cycles) comes from the battery controller and changes slowly over years. Hours are decided by what is running right now: the same full charge can last several times longer or shorter depending on the work. WattMate shows both sides: the battery's own readings, and the list of what is using the charge at this moment.

Often because it wakes. macOS gets woken while the lid is closed (by network traffic, Bluetooth and scheduled maintenance), and each wake costs charge. WattMate reads the macOS power log and names what woke the Mac, or the kind of wake when nobody scheduled it, how many times and for how long; what each single wake cost, it cannot measure. The most recent night is free to open.

No. The download is a single-architecture build for Apple silicon, so on an Intel Mac it won't launch at all. The energy counters it reads are part of Apple silicon too.

No. Since macOS 26.4, Apple silicon Macs cap charging natively between 80% and 100%, so a second switch beside Apple's own would add little.

Yes. WattMate's own item is a battery drawn the way macOS drew it before 27, with the percentage beside it as the same whole number macOS prints; the percentage is a toggle in Settings › General. To keep one battery, switch the system icon off in Control Center settings. macOS lists the apps using significant energy in its own battery menu, so hiding that icon hides the list from the menu bar too.

The yearly key stops unlocking the paid parts (the minutes, all runs and nights, the totals and how the battery ages), and the free part of the app keeps working. Run summaries stay on the Mac. The one-time key never expires.

The 2 measured quantities (the whole Mac's power and chip energy) come from your own hardware. Turning an app's chip energy into battery watts uses one rate on every Mac, a rounded 2 that tested mostly a little lower, and until the app has seen quiet minutes on your Mac it uses a default floor measured on ours. After that, the floor and the ratio between the chip's own processor meter and the apps' counters are learned on your Mac. What varies is how much of the total your screen takes, and an app's power use swings from minute to minute, which is why minutes are shown at the low end. How we count says where each figure comes from. We checked WattMate's numbers ourselves on 6 Macs in our lab: the app against each Mac's own power sensor, and that sensor against a USB-C meter not made by Apple. Rules, thresholds and scripts were published before the first counted run. On all 6 Macs, WattMate listed our test programs first, and Apple's sensor stayed within about 0.3 W of the meter (the results).

It costs a few thousandths of a watt (2 to 4.5 mW measured on a Release build of 1.5): even doubled by the rate of 2, about half a minute of battery over an 8-hour day at 8 W. It measures itself with the same instrument it measures everything else, and you can see its own line in the list, where the rate of 2 makes it about twice that.