About the Bike Computer
Introducing the Garmin Forerunner 645 Music. This music addition of the 645 has the great ability the hold up to 500 songs on the device, so you can now connect your favourite Bluetooth headphones, without having to connect to your phone to listen to your tunes. The watch features Garmin Pay, ready to make quick payments for when you don’t want to carry cash or cards whilst out for a run – just pay and run. Useful training data, such as ground contact time balance, stride length, vertical ratio and much more, are available to improve your performance to the best it can be, these functions are available with a heart rate strap or the compact running dynamics pod. The watch is designed to give you wrist-based heart rate recording to help you analysis your fitness overtime.

For analysing your performance after the 645 features a new monitoring tool called Training status, the can automatically evaluate your recent exercise history and performance indicators to tell you if your training productively, peaking or overreaching. The new anaerobic training effect metric opens a new insight to a critical dimension of training, telling you how your training is improving your ability to push the limits. You can even view your overall training load, which measures your exercise volume from the last 7 days and compares it to the optimal range for your fitness and recent training history. Still keeping you connected, the device allows you to receive and respond to text messages, find your phone, share live tracking with friends and family, and sync all your activities with Garmin Connect… and much much more. Overall the device allows you to train and feedback the best training method for you, whatever your sport.

Key Features


  • Battery life - up to 7 days in smartwatch mode; 5 hours in GPS mode.
  • Heart Rate - Uses wrist-based heart rate3 to offer performance monitoring features, including evaluating your current training status.
  • Running Dynamics - Provides advanced running dynamics2 including ground contact time balance, stride length, vertical ratio and more.
  • Garmin Pay - Includes the Garmin Pay™ Ready contactless payment method1 that lets you make convenient payments with your watch, so you can leave your cash and cards at home.
  • Download - Easily download up to 500 songs to your watch, and connect with Bluetooth® headphones (sold separately) for phone-free listening.

Garmin Forerunner 645 Music

Dimensions 42.5mm (L) x 42.5mm (W) x 13.5mm (D)
Battery Life - Smartwatch Mode: Up to 7 days
- GPS mode: Up to 14 hours
- GPS mode with music: Up to 5 hours
GPS Receiver Yes - GPS, GLONASS
Screen - Lens material: Corning® Gorilla® Glass 3
- Bezel material: Stainless steel
- Display type: Sunlight-visible, transflective memory-in-pixel
- Display size: 1.2" (30.4 mm) diameter
- Display resolution: 240 x 240 pixels
- Colour display
Features - Garmin Pay™
- Music
- Downloadable training plans
- Training status (lets you see if you’re training effectively by tracking your training history and fitness level trend)
- Training load (your total training load for the last 7 days calculated from estimated EPOC)
Workout Data - Step counter
- Move bar
- Auto goal
- Sleep monitoring
- Calories burned
- Floors climbed
- Distance travelled
- Intensity minutes
- TrueUp™
- Move IQ™
- Fitness age: Yes (in app)
- All-day stress tracking
Training Features - Auto Pause®
- Interval training
- Advanced workouts
- Auto Lap®
- Manual lap
- Configurable lap alerts
- VO2 max
- Training effect (aerobic)
- Training effect (anaerobic)
- Customisable alerts
- Audio prompts
- Finish time
- Virtual partner
- Race an activity
- Course guidance
- Segments (Live, Garmin)
- Strava features (Beacon, live segments)
- LiveTrack
- Touch and/or button lock
- Auto scroll
- Activity history on watch
Recording Features Barometric altimeter
Heart Rate Monitor Garmin Elevate™ wrist heart rate monitor
Bike Profiles - Preloaded cycling profiles: Biking, Indoor Biking
- Courses
- Race an activity
- Time/distance alerts
- Compatible with Varia Vision™
- Compatible with Varia™ radar
- Compatible with Varia™ lights
- Speed and cadence sensor support (with sensor)
Water Resistant Yes - 5 ATM
Connection Interface Bluetooth®, ANT+®, Wi-Fi®
(Connect IQ™ (downloadable watch faces, data fields, widgets and apps), Smart notifications, Text response/reject phone call with text (Android™ only))
Log History - 200 hours of activity data
- Download up to 500 songs
Compatibility iPhone® and Android™
Compatible with Garmin Connect™ Mobile
Straps Yes (20 mm, Industry standard), Silicone
Watch Functions Time/date
GPS time sync
Automatic daylight saving time
Alarm clock
Sunrise/sunset times
Controls smartphone music
Find my phone
Find my watch
VIRB® camera remote
Included in Box - Forerunner 645 Music
- Charging cable
- Documentation
Weight 42.2 g

Cyclister Group


Due to COVID-19, Orders placed outside of working hours will be processed the following day

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Customer Service




Cyclister Limited is a company registered in England and Wales with Company Number 11527831.

The Colour Shed Darley Abbey Mills, Darley Abbey, Derby, England, DE22 1DZ

Tel: +44 117 318 0511