# How to see which app uses the most energy on a Mac > Open Activity Monitor, click Energy, and sort by Energy Impact or 12 hr Power to find the apps draining your battery, and spot apps keeping the Mac awake. Canonical: https://www.notchstar.com/tips/see-which-app-uses-the-most-energy-on-mac/ Last updated: 2026-11-04 Published 2026-11-04. Open Activity Monitor, click the Energy tab, and click the Energy Impact heading to sort. The app at the top is using the most energy right now. On a Mac laptop the 12 hr Power column shows the average over the last 12 hours or since startup. ## Steps 1. Open **Activity Monitor** and click **Energy**. 2. Look at the list of apps above, and the energy information at the bottom. 3. Click a column heading to sort, for example **Energy Impact**. ## The columns, as Apple names them - **Energy Impact:** the app's current energy consumption relative to other apps. Lower is better. - **12 hr Power:** the app's average energy impact over the last 12 hours or since startup. It appears only on Mac laptops. Lower is better. - **App Nap:** whether App Nap is active for the app. - **Graphics Card:** whether the app needs a high performance graphics card. It appears only on Macs with one or more graphics cards. - **Preventing Sleep:** whether the app is keeping your Mac from sleeping. - **User:** the user name running the process. The number is a relative measure, so compare apps against each other rather than reading it as watts or a percentage. ## Battery details at the bottom On a Mac laptop, the bottom area shows **Remaining charge**, **Time until full** and **Time on AC** while plugged in, or **Time remaining** and **Time on battery** while unplugged. The **Battery (Last 12 hours)** graph shows the charge level over 12 hours. ## What you can do Apple's battery saving advice says to quit apps you are not using, because background apps can still use energy. If an app shows a high number and you do not need it, [quit it](https://www.notchstar.com/tips/quit-an-app-in-activity-monitor/). The **Preventing Sleep** column shows which apps are keeping your Mac from sleeping. Other items on Apple's list include lowering display brightness, turning off Bluetooth and WiFi when you do not need them, and disconnecting unused accessories. The [Low Power Mode tip](https://www.notchstar.com/tips/turn-on-low-power-mode-on-mac/) covers the energy mode setting, and [battery health](https://www.notchstar.com/tips/check-mac-battery-health/) covers wear. ## NotchStar's part NotchStar's [System tool](https://www.notchstar.com/features/system-stats/) shows totals only, with no per app or per process breakdown. It cannot tell you which app drains your battery. Use Activity Monitor for that. It samples readings once a second and only while its tab is open. ## Keep reading. - [CPU, memory, disk, battery and network](https://www.notchstar.com/features/system-stats/): Live CPU, memory, disk, battery and network speed gauges in your Mac notch. Sampling only runs while the tab is open, so it stays light. - [How to check your Mac battery health](https://www.notchstar.com/tips/check-mac-battery-health/): Open System Settings, Battery, and click the Info button beside Battery Health to see condition and maximum capacity. Also charge and longevity options. - [How to turn on Low Power Mode on a Mac](https://www.notchstar.com/tips/turn-on-low-power-mode-on-mac/): Choose Low Power under Energy Mode in System Settings, Battery, separately for battery and power adapter. Which Macs Apple says support it. - [How to check CPU and memory use on a Mac](https://www.notchstar.com/tips/check-cpu-and-memory-use-on-mac/): Open Activity Monitor and click CPU or Memory to see what is using your processor and RAM, and how to read memory pressure. - [How to quit an app that is using too much CPU](https://www.notchstar.com/tips/quit-an-app-in-activity-monitor/): Select the app in Activity Monitor, click the Stop button and choose Quit or Force Quit. What each does, and why not to force quit casually. ## More in System and battery. - [How to check CPU and memory use on a Mac](https://www.notchstar.com/tips/check-cpu-and-memory-use-on-mac/): Open Activity Monitor and click CPU or Memory to see what is using your processor and RAM, and how to read memory pressure. - [How to check your Mac battery health](https://www.notchstar.com/tips/check-mac-battery-health/): Open System Settings, Battery, and click the Info button beside Battery Health to see condition and maximum capacity. Also charge and longevity options. - [How to turn on Low Power Mode on a Mac](https://www.notchstar.com/tips/turn-on-low-power-mode-on-mac/): Choose Low Power under Energy Mode in System Settings, Battery, separately for battery and power adapter. Which Macs Apple says support it. - [How to quit an app that is using too much CPU](https://www.notchstar.com/tips/quit-an-app-in-activity-monitor/): Select the app in Activity Monitor, click the Stop button and choose Quit or Force Quit. What each does, and why not to force quit casually.