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, whether it is 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 pause, or a manual toggle. So if Keepresso itself is the reason, you see precisely why.

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.