Why won't my Mac sleep? See what is keeping it awake

When your Mac refuses to sleep, something is holding a power assertion, a request that tells macOS to stay awake, and it is not always obvious what. Keepresso shows you, in plain language.

Open the Activity pane

Keepresso's Activity pane lists every app currently holding your Mac awake, its live power assertions read straight from the system. It is a readable version of what pmset -g assertions prints in Terminal, so you can see exactly who is keeping the Mac up: Keepresso, a browser, a download manager, a video app, or something you forgot was running.

The decision log

Alongside it, a decision log shows why each Keepresso session started or stopped: which trigger fired, a timer running out, a battery or thermal pause, or a manual toggle. So if Keepresso itself is the reason, you see precisely why. The log survives a relaunch, and a simple seven-day summary shows how long Keepresso held the Mac awake, with the battery drop when both ends of a session had a reading.

Common culprits

• A browser tab playing audio or video.
• A download or a sync still finishing.
• A backup or a long-running app.
• A Keepresso trigger whose condition is still true (the Activity pane and log make this clear).

Once you know what is holding it, quit that app, finish the task, or adjust the trigger, and your Mac sleeps again.

Frequently asked

How do I check what is keeping my Mac awake without an app? In Terminal, pmset -g assertions lists every active power assertion and the process behind it. Keepresso's Activity pane is the same information in plain language, so you do not have to read the raw output.

Why does my Mac wake up on its own at night? That is usually a scheduled event rather than something holding it awake: a Time Machine backup, Power Nap, a "wake for network access" request, or a Bluetooth device nudging it. pmset -g log shows the wake reason; the Activity pane shows anything keeping it up once it is awake.

Closing the lid does not put it to sleep. Why? Something is still holding an assertion, or the Mac is in closed-display mode because it is on power with a display or keyboard attached. Check the Activity pane first; if Keepresso's own closed-display mode is on, that is expected behavior.

Is a stuck power assertion bad for the Mac? It does no harm, but it drains the battery and defeats sleep until the app releases it or you quit it. Seeing it in the Activity pane is the fastest way to end it.