Fitbit Flex has a rechargeable battery that generally lasts for 5 days. For more information about the Flex's battery, see Tracker battery information. For troubleshooting, see My tracker's battery isn't charging.
To charge your Flex, do the following:
- Remove your tracker from the wristband:
- Insert your tracker into the charging cable. Line up the tracker with the charging cable, putting the rounded end of the tracker into the charging cable at a slight angle. Use your thumb to push the tracker in and down into the charging cable until you hear a click.
- Insert the charging cable into a USB port or UL-certified USB wall charger.
- Your Flex's LED indicator lights will pulse to show the battery level every few seconds.
Each solid indicator light represents progress towards the total charge. It may take up to 3 hours to fully charge your Flex. When it's charged, all 5 indicator lights will blink.
- You can then take your tracker out of the charging cable and insert it into your wristband.