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Mac fan is loud even with no apps open

A loud fan with nothing open means something is running in the background. Open Activity Monitor and look at the CPU tab. Whatever has the highest percentage is using your processor.

Mac fans run because background processes are using CPU power. If the fan is loud with nothing open, Spotlight is indexing, an app is stuck, or malware is running. Activity Monitor shows you exactly what's using power. Find the offender and stop it.

Risk: Medium ⏱ 10–20 minutes Beginner
⚡ Before you start
  • Have Activity Monitor ready to open (Command+Space, type Activity Monitor)
  • Keep some time free to let Spotlight finish indexing if that's the cause
  • Note any apps or processes you don't recognize so you can look them up

Fix-IT-Bot will walk you through each step, just tap, no typing needed.

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