Track steps, distance, calories burned & active minutes
See LEDs light up as you progress toward your daily goal
Sync stats wirelessly & automatically to leading smartphones and computers
Style + Accessories
Style the slim, removable tracker your way with Flex accessories from Fitbit and Tory Burch
Wear + Life
Water - resistant wristband with a 5-day battery life
Auto Sleep + Alarms
Monitor your sleep automatically & set a silent alarm
Set a goal and go.
Stay focused on your goals and get motivated to be more active with Flex—a slim, stylish device that tracks all-day activity like steps taken, distance traveled, calories burned and active minutes.
See your day in a whole new light.
Flex lets you see how every day is stacking up with LEDs that light up like a scoreboard as you get 20% closer to completing your step, calorie or distance goal.
Step. Sleep. Wake. Repeat.
Fitbit Flex automatically tracks how long and how well you sleep—no tapping necessary—so you can monitor your sleep trends without interrupting your nighttime routine. It also includes a silent, vibrating alarm to make your wake-up call more peaceful.
Wear Flex your way, every day.
Style your Flex tracker with bright accessory bands, or turn it into a fashion piece with our exclusive Flex collection from Tory Burch. To change bands, simply pop the slim Flex tracker out of your wristband and slip it into the accessory that fits your personality.
All your stats, always in sync.
Flex syncs your daily stats to your computer and over 150 leading smartphones, and shows your progress in easy-to-read charts and graphs, to give you the push you need to keep moving toward your goals.
With you all the time.
Flex fits comfortably around your wrist, is water-resistant, and has a 5-day battery life, so you can wear it day to night. And with a variety of available accessory bands, you’ll find the right Flex for every occasion.
View your progress and analyze your trends with easy-to-read charts and graphs
Compete in challenges
Invite friends and family to share stats, send cheers & taunts,& compete on the leaderboard
Log food fast with a barcode scanner, calories estimator, meal shortcuts & expanded food database
Log workouts, see a monthly exercise calendar, & use MobileRun to track run stats and map routes
Get goal progress notifications & celebrate fitness milestones with badges
Set sleep goals, review sleep quality & see weekly sleep graphs.
Sensors and Components
- 3-axis accelerometer
- Vibration motor
- LED display with 5 white indicator lights
- Tap twice to see progress against your Main Goal
- Tap rapidly for 1-2 seconds to start or stop sleep tracking
Flex has been tested up to 1 ATM meaning it is sweat, rain and splash proof. However, the device is not swim proof. We also recommend taking Flex off before showering because, as with any wearable device, it’s best for your skin if the band stays dry and clean.
If the band gets wet or if you sweat in it, remove and completely dry the band before putting it back on. Clean the band with a mild soap-free cleanser like Cetaphil Gentle Skin Cleanser or Aquanil. Give your wrist a rest by taking the band off every now and then. Learn more.
The Flex wristband is made of a flexible, durable elastomer material similar to that used in many sports watches. Flex also has a surgical-grade stainless steel clasp.
Battery and Power
We recommend charging your Flex every few days to ensure you are always tracking.
- Battery life: up to 5 days
- Battery type: Lithium-polymer
- Charge time: One to two hours
- Radio transceiver: Bluetooth 4.0
- Operating temperature: -20° to 45 °C
- Maximum operating altitude: 9.144 km
- Tracks 7 days of detailed motion data, minute by minute
- Tracks daily totals for past 30 days
Flex syncs automatically and wirelessly to tablets, computers and 150+ leading iOS, Android and Windows smartphones using Bluetooth 4.0 wireless technology.
- Syncing range: 6 m
- Syncing to computers requires Internet connection and USB port
- Syncing to mobile devices requires Bluetooth and Internet connection
- Syncs with Windows Vista and later, Mac OS X 10.6 and up, iPhone 4S and later, iPad 3 gen. and later, and leading Android and Windows devices