Open Activity Monitor first.

Open Activity Monitor first.

Even “light use” can hammer your battery if something is sucking power in the background. Think browser tabs with ads, Slack, Zoom, or Mail indexing. These don’t look like heavy work but they keep the CPU awake.

Go to Applications > Utilities > Activity Monitor. Click the “Energy” tab. Sort by “Energy Impact” and look for anything using more than 20 when you’re not doing anything obvious. Chrome and its extensions are usually the worst offender — even with a few tabs open. Zoom and Slack are also notorious. Kill those, and your battery should settle down.

If nothing stands out, check if Spotlight is re-indexing (happens after an update) or if you have a rogue widget chewing power. Sometimes it’s just a bad app version.

Once you find the culprit, either quit it or set preferences to reduce background activity. Future You will get an extra hour or two.