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Identify patterns of stress with all-day body response tracking and smart notifications to remind you to reflect on your emotions. Try new ways of managing stress with guided breathing, exercise, meditations and more.
Sleep Profile and Sleep Score give insights for better sleep.
Sleep Profile9 breaks down your sleep data each month and pinpoints how you can improve sleep based on 10 key sleep metrics.
Check your Sleep Score to learn about the quality of your previous night's sleep, and get a breakdown of time in light, deep, and REM sleep with Fitbit Premium.2
Focus on your heart with the ECG app and heart rate tracking.
Use the ECG app for on-demand atrial fibrillation assessment or turn on irregular heart rhythm notifications to assess your heart rhythm while you're still or sleeping.3
Heart rate tracking surfaces insights from your sleep, stress, activity, and more while high and low heart rate notifications keep a close eye on your heart.
Get more out of your workouts.
Your Daily Readiness Score analyzes recent activity, sleep, and heart rate variability. Maybe you’re signed up for a HIIT class but change plans after seeing your score – Fitbit Premium serves up a yoga flow for you.2
Help from Google Maps and Google Wallet.
Reach your destinations easier with turn-by-turn directions from Google Maps.5 Make speedy, secure checkouts from your wrist with Google Wallet.4
Features | |
---|---|
Waterproof up to | 50 m |
Heart rate monitor | Yes |
Ambient light sensor | Yes |
Thermometer | Yes |
Altimeter | Yes |
Built-in camera | No |
Vibrating motor | Yes |
FM radio | No |
Mobile operating systems supported | Android, iOS |
Operating system installed | Fitbit OS |
Built-in microphone | Yes |
Touchscreen | Yes |
Built-in speaker(s) | Yes |
Short Message Service (SMS) | Yes |
Display type | Digital |
Accelerometer | Yes |
Quality of sleep | Yes |
Virtual assistant | Amazon Alexa |
Smart notifications | Yes |
Answerphone remote access | Yes |
Activity tracker | Yes |
Heart rate sensor type | Optical |
Distance travelled | Yes |
Calories burned | Yes |
SMS notifications | Yes |
Vibrating alarm clock | Yes |
Blood pressure monitor | Yes |
Country of origin | United Kingdom |
Always-on display | Yes |
Blood oxygen sensor | Yes |
Skin temperature sensor | Yes |
Workout tracking | Yes |
Find my phone function | Yes |
Call notifications | Yes |
Automatic daily activity detection | Yes |
Alarm clock | Yes |
Advanced workouts | Yes |
Technical details | |
Heart rate monitor | Yes |
Ambient light sensor | Yes |
Thermometer | Yes |
Altimeter | Yes |
Waterproof up to | 50 m |
Product colour | Black |
Built-in camera | No |
Watch glass type | Corning Gorilla Glass 3 |
Vibrating motor | Yes |
FM radio | No |
Protection features | Water resistant |
Shape | Square |
Band colour | Black |
Mobile operating systems supported | Android, iOS |
Operating system installed | Fitbit OS |
Built-in microphone | Yes |
Touchscreen | Yes |
Built-in speaker(s) | Yes |
Short Message Service (SMS) | Yes |
Display type | Digital |
Accelerometer | Yes |
Quality of sleep | Yes |
Virtual assistant | Amazon Alexa |
Smart notifications | Yes |
Answerphone remote access | Yes |
Display | |
Watch glass type | Corning Gorilla Glass 3 |
Touchscreen | Yes |
Display type | Digital |
Always-on display | Yes |
Colour display | Yes |
Design | |
Market positioning | Smartwatch |
Watch case colour | Black |
Watch case material | Aluminium |
Band size | S/L |
Wrist size range | 129 - 209 mm |
Waterproof up to | 50 m |
Product colour | Black |
Protection features | Water resistant |
Shape | Square |
Band colour | Black |
Closure type | Single prong strap buckle |
Maximum strap length | 20.9 cm |
Suggested gender | Unisex |
Minimum strap length | 12.9 cm |
Waterproof | Yes |
Watch glass type | Corning Gorilla Glass 3 |
Performance | |
Built-in camera | No |
FM radio | No |
Mobile operating systems supported | Android, iOS |
Operating system installed | Fitbit OS |
Built-in microphone | Yes |
Built-in speaker(s) | Yes |
Network | |
GLONASS | Yes |
GPS (satellite) | Yes |
Mobile network connection | No |
Ports & interfaces | |
USB port | No |
Near Field Communication (NFC) | Yes |
Bluetooth | Yes |
Wi-Fi | No |
Bluetooth version | 5.0 |
Headphone connectivity | Bluetooth |
Bluetooth Low Energy (BLE) | Yes |
Power | |
---|---|
Charging time | 2 h |
Battery technology | Lithium Polymer (LiPo) |
Battery life (max) | 144 h |
Battery life (GPS mode) | 5 h |
Battery type | Built-in battery |
Battery life | 6 day(s) |
Battery life | 144 h |
Operational conditions | |
Operating temperature (T-T) | -10 - 45 °C |
GPS Performance | |
GLONASS | Yes |
GPS (satellite) | Yes |
Other features | |
Product colour | Black |
Bluetooth | Yes |
Protection features | Water resistant |
Weight & dimensions | |
Width | 91 mm |
Depth | 176 mm |
Thickness | 6.6 cm |
Weight | 200 g |
Packaging data | |
Package width | 194 mm |
Package depth | 219 mm |
Package height | 369 mm |
Packaging content | |
Charging base | Yes |
Charger | Yes |
Logistics data | |
Harmonized System (HS) code | 8517620000 |
SKU | FB521BKGB | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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EAN | 0810038858364 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Specification |
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Manufacturer | Fitbit | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
In Stock | N |