Mountain Equipment Company

Garmin Forerunner 45S



Regular colours

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Shop with confidence. If it’s not working out, you can return it (consumables, electronics, undergarments and swimwear excluded).
Really. If it's not up to snuff after you use it (a couple times) you can still bring it back. It lasts longer than 30 days, but not forever. We'll be fair about it.


The Forerunner 45S personalizes how you train. See how your body responds to exercise, rest and sleep. The optical heart rate monitor takes your pulse straight off your wrist, no need for a chest strap. Running metrics like speed and distance are handled by the onboard GPS and internal accelerometers, turning movement into data and crediting all you do in the gym or trails. Pairing your phone via Garmin Connect to opens a world of smartwatch functionality. Review activities, receive notifications (texts, social media alerts, email), download training plans, keep an eye on the weather, control music apps, and share milestones and encouragement with an online community.

  • Built-in activity modes for biking (outdoor), running (outdoor) and walking, with more activities unlockable through free the Connect app, like elliptical training, biking (indoor), running (indoor) stair stepping, yoga and more
  • Internal antenna connects to 3 satellite constellations, GPS, GLONASS and Galileo for a fast connection and a strong GPS signal
  • Internet Live Tracking shared location and heart rate data with friends, family, or coaches via your phone
  • Equipped with Garmin’s new V3 low-profile Elevate™ optical heart rate monitor which provides more reliable constant heart rate data and allows you to train without a chest strap
  • Broadcast of your HR over ANT+
  • VO2 max data lets you see how efficiently your body uses oxygen
  • Incident detection: in case of accident, the unit sends a signal through your phone to your emergency contacts
  • Assistance mode sends a message to emergency contacts via phone
  • Body Battery™ mode tracks your energy levels throughout the day. By monitoring what drains your energy (exercise) and recharges your energy (rest, food, etc.), you get a better idea of how, and when to train
  • Garmin Coach provides free, personalized training plans that you can download through Garmin Connect
  • Stress level score monitors heart rate variability while inactive to guide you to reduce stress
  • 24/7 activity tracking and step counting, 45S 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 total sleep and restful sleep
  • Smart notifications (emails, texts, alerts and more) come in via Bluetooth connection to your smartphone
  • Automatically sync your data to a paired smartphone running the free Garmin Connect app
  • Connects with ANT+ and Bluetooth Smart, from foot pods, to speed and cadence pods (not power meters or Varia lights)
  • Connect IQ support to download custom watch faces
  • Intuitive 5-button interface works with gloves and in all weather conditions
  • 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
  • Rechargeable lithium-ion battery lasts up to 13 hours in GPS mode or up to 7 days in smartwatch mode
  • Fits wrist circumference of 124-185mm
  • In the box: Forerunner 45S, charging cable and documentation

Tech specs

Weight32g (White)
32g (Black)
Ideal for
  • Running, fitness and training
  • Cycling
  • Casual wear
Wrist strap materialSilicone
Mineral crystal glass
Dimensions4 x 1.2cm
Countdown timerYes
Data cardNot accepted
Touch screenNo
Interval trainingYes
BatteriesLithium-ion (included)
Distance/time alarmYes
Battery life13-168 h
Wireless syncYes
Metric/imperial units formatYes
  • USB
  • Wireless
Button lockYes
12/24 hour formatYes
Battery power indicatorYes
Low battery warningYes
Case diameter40mm
Sold separately
Workout historyYes
Replaceable wrist strapYes
Not compatible
Tide tablesNo
  • Garmin Connect
Sold separately
Chest strapSold separately
Area calculationNo
Heart rate monitorYes
Haptic feedbackYes
Made inTaiwan

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4 out of 5 stars with 326 reviews for Garmin Forerunner 45S

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