Craig Mercure 
If your FitBit Flex is not working properly, or if you want to make sure that you have the latest and greatest version of the firmware, you can update it yourself. Here’s how:
- Charge your Fitbit Flex completely. You can’t update the firmware if your device isn’t fully charged.
- Connect your Fitbit Flex to the charging cable, and then plug the charging cable into your computer.
- Download the Fitbit Connect software from the Fitbit website. If you already have Fitbit Connect installed, make sure that it’s up to date.
- Open Fitbit Connect and log in with your Fitbit account information.
- Click the device icon in the upper-left corner of Fitbit Connect and then click Check for device update. If an update is available, you’ll see a notification message.
- Click Update and follow the on-screen instructions. Do not disconnect your Flex during the firmware update process.
How to update Fitbit
firmware
- Connect your Fitbit device to the charger, then plug the charger into a USB port on your computer before proceeding.
- Head to the Fitbit app dashboard and click the device icon in the top-right corner.
- Select your device from the list that appears and scroll down to find the Update Firmware button near the bottom of the page.
- Click it and wait for the firmware update process to begin—it shouldn’t take more than a few minutes.
- Once it’s done, you’ll see a confirmation message on-screen letting you know that the process is complete.
What is firmware and why do you need to update it?
Firmware is the low-level software that helps your Fitbit device run. From time to time, we release free software updates that add new features and functionality, and improve performance. In some cases, these updates also address known issues and bugs. When you update the firmware on your Fitbit device, you’ll also get all the latest software features.
You should update your firmware whenever there’s a new version available. For example, if you’re experiencing an issue with your Fitbit device that isn’t resolved by a restart or battery cycle, updating the firmware may address it. Firmware updates can also improve battery life and performance.
To update your firmware:
Make sure your device is connected to the charger, then plug the charger into a USB port on your computer before proceeding. Head to the Fitbit app dashboard and click the device icon in the top-right corner. Select your device from the list that appears and scroll down to find the Update Firmware button near the bottom of the page. Click it and wait for the firmware update process to begin—it shouldn’t take more than a few minutes. Once it’s done, you’ll see a confirmation message on-screen letting you know that the process is complete.
What to do if your FitBit Flex doesn’t update properly
If for some reason your FitBit Flex doesn’t update properly, don’t worry. Here are a few things you can try: Restart your device by holding down the button for 10 seconds. Unplug and replug your device into the charging cable. Try updating again from the Fitbit app dashboard. If all else fails, you can contact Fitbit customer support for help.
