AirTags use CR2032 coin cell batteries, the same type found in watches and calculators

An AirTag holds one CR2032 battery, a small round coin cell about the size of a dime. This is a standard battery type you can find at any drugstore, supermarket, or hardware store—not a proprietary part made only by Apple. The battery sits in a slot under the white plastic disc on the back of the AirTag, held in place by a small metal contact.

The CR2032 designation tells you the battery's chemistry and dimensions. "CR" means it uses lithium chemistry, and "2032" refers to its size: 20 millimeters in diameter and 3.2 millimeters thick. Because this is a common battery type, you have many brands to choose from when it's time to replace it.

Key Takeaways

  • AirTags use one CR2032 coin cell battery, a standard type sold at most stores for a few dollars.
  • A fresh CR2032 battery lasts about one year in an AirTag under normal use, though this varies based on how often you trigger the sound or check its location.
  • You can replace the battery yourself by twisting off the back disc and swapping in a new CR2032—no tools or technical knowledge required.
  • When the battery runs low, your iPhone sends you a notification, giving you time to buy a replacement before the AirTag stops working.

How long a CR2032 battery lasts in an AirTag

Apple states that a CR2032 battery lasts approximately one year in an AirTag. This estimate assumes typical use—checking the AirTag's location occasionally through the Find My app and using the sound feature a few times a month. If you trigger the sound alert frequently or check the location constantly, the battery will drain faster. If you rarely use the sound or check the location, it may last longer than a year.

The actual lifespan also depends on the specific battery brand you use. Some CR2032 batteries are rated for higher capacity than others. A battery from a major manufacturer like Energizer or Duracell will generally perform as well as any other, but off-brand or very old stock may not hold a full charge.

How to replace the battery yourself

Replacing an AirTag battery takes less than a minute and requires no tools. Hold the AirTag with the white plastic side facing you. Place your thumb on the metal ring around the edge and twist it counterclockwise until you hear a click. The white disc will pop off, revealing the battery underneath.

Lift out the old CR2032 battery and insert the new one with the positive side (marked with a "+") facing up toward you. Press the white disc back onto the AirTag and twist it clockwise until it clicks into place. Your AirTag will reconnect to your iPhone automatically within a few seconds.

Where to buy CR2032 batteries

CR2032 batteries are sold almost everywhere. You can find them at drugstores like CVS and Walgreens, supermarkets, hardware stores, and online retailers. A single CR2032 typically costs between $2 and $5, depending on the brand and where you buy it. Buying a multi-pack is usually cheaper per battery if you have multiple devices that use them.

Common brands include Energizer, Duracell, Panasonic, and Sony. Store brands work just as well and often cost less. Avoid extremely cheap batteries from unknown manufacturers, as they may not hold their rated capacity.

What happens when the battery gets low

Your iPhone will send you a notification when an AirTag's battery is running low, typically when it has a few weeks of charge remaining. This gives you time to purchase a replacement battery before the AirTag stops working entirely. You can also check the battery level manually by opening the Find My app, selecting the AirTag, and looking at the battery indicator at the top of the screen.

Once the battery is completely dead, the AirTag will no longer communicate with your iPhone or other Apple devices. It will not send location updates, and the sound feature will not work. Replacing the battery restores full function when ready.

Why Apple chose the CR2032

Apple selected the CR2032 because it balances size, power output, and availability. The battery is small enough to fit inside an AirTag's compact case, yet powerful enough to support Bluetooth communication and a speaker for a full year. Because CR2032 batteries are used in thousands of other devices—watches, calculators, car key fobs, hearing aids—they are inexpensive and available everywhere, making replacement straightforward for users.

This choice also means you are not locked into buying batteries from Apple or a specific retailer. Any CR2032 from any manufacturer will work in your AirTag.

Frequently Asked Questions

Can I use a rechargeable CR2032 battery in my AirTag?

Rechargeable CR2032 batteries exist, but they are not recommended for AirTags. Rechargeable versions have a lower voltage output than standard CR2032 batteries, which can cause the AirTag to behave unpredictably or drain the battery faster. Stick with standard single-use CR2032 batteries for reliable performance.

What if I lose the white plastic disc when I open my AirTag?

If you lose the disc, you can order a replacement from Apple or find third-party replacements online. The disc is not essential for the battery to work—the battery will function without it—but the disc protects the battery from dirt and accidental contact. You can also use a small piece of tape to hold the battery in place temporarily.

Does temperature affect how long the battery lasts?

Yes. Cold temperatures slow down the chemical reaction inside the battery, reducing its output temporarily. Hot temperatures can speed up the reaction but may also shorten the battery's overall lifespan. Store your AirTag in a normal room temperature environment for the best battery performance.

Can I use an old CR2032 battery from another device in my AirTag?

You can, but it is not ideal. If the battery has already been used in another device, it has less remaining charge than a fresh battery. It will work, but it may not last the full year. Use a fresh battery for the longest lifespan.