• Fitbit Sense™
• Classic wristband (both small & large)
• Charging cable

• Multi-path optical heart rate sensor
• Multipurpose electrical sensors compatible with ECG app & EDA app
• Red and infrared sensors for oxygen saturation (SpO2) monitoring
• Gyroscope
• Altimeter
• 3-axis accelerometer
• Skin temperature sensor
• Ambient light sensor
• Wi-Fi (802.11b/g/n 2.4GHz)
• NFC
• Built-in GPS + GLONASS
• Vibration motor
• Speaker (75dB SPL @10cm)
• Microphone

Battery life up to 6+ days. Battery life and charge cycles vary with use, settings, and other factors; actual results will vary. Use of the always-on display and SpO2 features will require more frequent charging. We recommend charging every few days to ensure you’re always tracking.

• Battery type: Lithium-polymer
• Charge time: (10-80%): Approximately 40 minutes
• Fast charging: 1 day of battery life in 12 minutes
• Radio transceiver: Bluetooth®

• Saves 7 days of detailed motion data, minute by minute
• Saves daily totals for past 30 days
• Stores heart rate data at 1 second intervals during exercise tracking and at 5 second intervals all other times

Water resistant to 50 meters. After getting the band wet, we recommend drying the band because, as with any wearable device, it's best for your skin if the band is clean and dry.

Give your wrist a rest by taking the band off every now and then. If the band gets wet or you sweat in it, remove and completely dry the band before putting it back on. 

This watch includes a band made of a flexible material similar to that used in many sports watches, as well as an aluminum watch case and buckle.

Like all heart rate tracking technologies, accuracy is affected by physiology, location of device and different movements.

• Operating temperature: 14° to 113°F
• Maximum operating altitude: 28,000ft

The Fitbit app is compatible with most popular phones. To set up and use your Fitbit products and services, you must install the Fitbit app on a compatible device running one of the following operating systems:

• Apple iOS 12.2 or higher.
• Android OS 8.0 or higher. See additional tips for Android phones 

Syncing range: Up to 30ft

• Certain features like smartphone notifications may require Android 8.0+.
• Syncing requires Bluetooth® LE and internet connection.
• Syncs with Mac OS X 12.2 and up, iPhone 5S and later, Android 8.0 and later.
• Music control via Bluetooth® Classic on Android and Bluetooth LE on iOS devices.

Print this guide to find the right size for you. Both small and large sizes included inbox.

Small

• Fits wrist 5.5" - 7.1" in circumference

Large

• Fits wrist 7.1" - 8.7" in circumference

Dimensions

• 1.59in l x 1.59in w x 0.49in h