To get the most out of your battery, make sure your Zip is using the latest firmware version. You can check for an update by following the instructions in our How do I update my tracker using a computer?
The Fitbit Zip runs on a replaceable 3V coin battery, CR2025 (pictured below). It can be found wherever batteries are sold.
Your Zip's battery should last 6 months with regular use.
When the battery drops below 25%, a low battery indicator will show on the display of your Zip, as well as on your Fitbit.com profile. A flashing battery icon indicates that your Zip is very close to being completely out of battery life, so it should be replaced very soon. Data could be lost if your Zip is not synced before you replace the battery.
If your Zip's battery drains, purchase a new 3V coin battery, CR2025. Use the battery door tool (pictured below) to open and close the battery door compartment, which is located on the back of the Zip. Your old battery can be recycled.