1. How long it lasts
Apple gives the AirTag battery a life of about a year. Heavy use, such as frequent sound alerts or constant movement, can shorten it.
2. The battery it takes
The AirTag takes a 3-volt CR2032 coin cell. Apple warns that some CR2032 cells with a bitter coating may not work, so use an uncoated one if your AirTag seems dead.
3. Open the back
Press down on the stainless steel back, turn it counterclockwise until the lock symbol lines up, and lift the cover off. Then take out the old battery.
4. Fit the new one
Put the new battery in with the positive side facing up, the side with the writing. Line up the cover’s tabs with the slots, press down and turn it clockwise until it stops.
5. Check it works
Bring the AirTag close to your iPhone, or open Find My, to confirm it responds. If it doesn’t, check the battery is seated and the cover is locked, then try again.