Why does my laptop fan run all the time?

Your laptop fan usually runs all the time because the CPU or GPU is staying warm and the system is trying to keep it cool.

Most common causes:

• Blocked vents or dust — soft surfaces, dust, or pet hair can trap heat.
• Heavy background activity — updates, lots of browser tabs, or a program using high CPU.
• Aggressive power settings — performance mode can keep the fan active more often.
• Malware or crypto-miners — hidden software can quietly max out the processor.
• Outdated BIOS/drivers — bugs can make the fan curve behave badly.
• Old thermal paste — on older laptops, heat transfer can get worse over time.

What to do:

1. Use the laptop on a hard, flat surface.
2. Check CPU usage in Task Manager or Activity Monitor.
3. Switch to Balanced or Battery Saver mode.
4. Clean the vents with compressed air.
5. Run a malware scan.
6. Check for BIOS and driver updates.

If the fan is loud even when the laptop is idle, or the machine feels hot to the touch, the cooling system may need cleaning or service.