Mountain Equipment Company

Garmin Forerunner 645 Music - Unisex


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Run free: no cords, no chest strap, no wallet. The Forerunner 645 Music stores up to 500 songs and plays them over Bluetooth so there are no cords to hold you back. The Elevate optical heart-rate monitor reads your pulse information straight off your wrist. GPS and an internal accelerometer track running metrics like speed and distance information, turning your movement into data and making sure you get credit for your work in the gym and on the trails. If you're going to carry your phone anyway, pair the 645 with the free Garmin Connect app to review your performance, receive notifications, control certain other apps, and more. Strava live segment integration (requires Strava premium) uses the power of your smartphone to show you nearby segments as you run. On-the-fly integration means that you no longer have to pre-load your segments, though starred segments will still appear like you’re used to.

  • Built-in activity modes for biking, running, walking, swimming (indoor only), strength training (with rep counter), and more (no multisport mode)
  • Download playlists and podcasts via Spotify, iHeartRadio or Deezer streaming services, or drag and drop MP3s from your computer through Garmin Express
  • Playlists synced from streaming services can be easily updated on your watch when in range of known Wi-Fi networks
  • Holds up to 500 songs (depending on music quality), or 3.5GB of music data
  • Lap data can be configured to come through your headphones, letting you know your pace, speed and more
  • Garmin Pay™ contact-less payment system (coming soon), will let you pay for purchases through convenience of NFC. By linking credit cards to your Garmin account though Garmin Connect, you can make payments with your watch (if supported by your bank)
  • Internet Live Tracking during activities (through a connected smartphone) allows you to share your location and heart rate with friends, family or coaches
  • Equipped with Garmin’s new lower-profile Elevate™ optical heart-rate monitor, which provides more reliable constant heart-rate data and allows you to train without a chest strap
  • Optical heart-rate sensors measure changes in blood volume under the skin and work best when worn snugly, 1 to 3 finger-widths above your wrist bone
  • Firstbeat™ bullet provides physiological metrics including VO2 max, lactate threshold (requires a heart-rate chest strap, sold separately), race predictor, recovery advisor and performance indicator
  • Strava Segment integration – both pre-loaded and on-the-fly (through connection with your phone) – lets you know when your starred segment is about to begin and shows instantaneous data, not just of your performance in the moment, but also how it compares to your PR and the current KOM or QOM, and then provides results once the segment is complete (requires Strava premium)
  • Navigate through courses created or downloaded through Garmin Connect or Strava
  • Training status uses data from past workouts to learn your fitness level and tell you whether or not the training you are doing is productive
  • Broadcasts your heart rate over ANT+ so other devices can pick it up
  • Through 24/7 activity tracking, Forerunner 645 learns your activity level and helps guide you towards a more active lifestyle
  • Move bar reminds you to move after being stationary for too long
  • On-board sleep tracking mode monitors your rest, letting you see your total sleep hours as well as periods of movement and restful sleep in your Garmin Connect profile
  • Weekly intensity minutes are displayed against the ideal of 150 needed to maintain a healthy life
  • Intuitive 5-button interface is easy to use in any weather
  • Automatically sync your data to a paired smartphone running the free Garmin Connect app
  • Compatible with all smartphones featuring Bluetooth 4.0 (iPhone 4S or higher, and Android 4.3 or higher)
  • Connects with ANT+ and Bluetooth Smart sensors, from foot pods to speed and cadence pods (but not power meters)
  • Connect IQ support allows you to download apps, templates, data fields, watch faces, and other features
  • Barometric altimeter helps you track your ascents, descents and total elevation changes
  • Always-on colour display is bright and clear in any conditions
  • Internal memory stores up to 200 hours of activities. Garmin Connect will store all of your activity data
  • User-friendly strap changes, thanks to quick-release pins
  • Rechargeable lithium ion battery lasts up to 12 hours in GPS mode or 5 hours in GPS and music mode, and up to 7 days in smartwatch mode
  • In the box: Forerunner 645 Music, charging cable and documentation

Tech specs

Weight43g (Silver/Black)
43g (Silver/Cerise)
Ideal for
  • Running
  • Fitness and training
Wrist strap materialSilicone
Mineral crystal glass
Built-in memory4GB
Dimensions4.3 x 4.3 x 1.4cm
Countdown timerYes
Data cardNot accepted
Touch screenNo
Interval trainingYes
BatteriesLithium-ion (included)
Distance/time alarmYes
Battery life5-160 h
Wireless syncYes
Metric/imperial units formatYes
  • USB
  • Wireless
Button lockYes
12/24 hour formatYes
Battery power indicatorYes
Lug width20mm
Low battery warningYes
Case diameter43mm
Sold separately
Workout historyYes
Replaceable wrist strapYes
Not compatible
Tide tablesNo
  • Garmin Connect
  • Third party apps
Sold separately
Chest strapSold separately
Area calculationNo
Heart rate monitorYes
Haptic feedbackYes
Made inTaiwan

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3 out of 5 stars with 127 reviews for Garmin Forerunner 645 Music - Unisex

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