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Whats in the box:

Garmin Forerunner 645 Music Sport Watch

Charging Cable


Built-In Music Storage

Advanced Multi-Sport Data and Statistics

Wrist-Based Heart Rate Monitor

1.2″ Color Display

Activity Tracker Functions

Real-Time Training Status & Monitoring

Bluetooth, ANT+, & Wi-Fi Connectivity

GPS & GLONASS Supported

Built-In Accelerometer & Barometer

Smart Notifications


Lens Material Chemically strengthened glass

Bezel Material Stainless steel

Band Material Strap Material: silicone

Quick Release Bands: yes (20 mm, industry standard)

Water Rating 5 ATM

Display Type Sunlight-visible, transflective memory-in-pixel (MIP)

Display Size 1.2″ / 30.4 mm diameter

Display Resolution 240 x 240 pixels

Battery Life Smartwatch Mode: up to 7 days

GPS Mode: up to 14 hours

Memory 200 hours of activity data

Dimensions 1.7 x 1.7 x 0.5″ / 4.3 x 4.3 x 1.4 cm

Weight 1.5 oz / 41.8 g

Track your runs, gym workouts, outdoor recreational activities, bike rides, laps in the pool, and more with the Garmin Forerunner 645 Sport Watch. For added motivation Garmin has developed their own online community, simply download the Garmin Connect Mobile app and sync your data to see how you stack up against others within the social community.

Not only does the Garmin Forerunner 645 just track your activities, it provides deep analysis and insight so you can digest the data. Customizable data pages and activity profiles make it easy to display your data the way you want to see it. You can easily see your GPS speed and distance, your interval training and advanced workout statistics, your VO2 max., your training status, your aerobic and anaerobic training effects, the activity history on the watch, and much more.

In addition to intuitive analysis of your activities, the Garmin Forerunner 645 features a number of heart rate features including HR zones, HR alerts, HR calories, % HR max., % HRR, recovery time, auto max HR, and HR broadcast.

Did you leave your wallet at home while on that run? The Garmin Forerunner 645 has you covered with the Garmin Pay contactless payment solution, which allows you to just tap your watch and go. You can also receive text messages, social media updates, emails, and more right from your sport watch.

Paying Made Easy

The Forerunner 645 Sport Watch features the Garmin Pay contactless payment solution, which lets you pay for purchases with your watch. Use it just about anywhere you can tap your card to pay.


With up to 500 songs worth of music storage built right into your watch, put the “beat” in your daily mission to beat yesterday. It’s easy to transfer music from your computer and then queue up your favorite playlist for easy listening through Bluetooth headphones. You can even sync your carefully crafted playlists from select music streaming services to your watch for more ad-free listening. Now you really can leave your phone behind when you head out for a run, because the music that helps keep you moving is right there on your wrist.

Tune up Your Training

Let the Forerunner 645 Sport Watch measure crucial running metrics that you can use to analyze your performance. Biomechanical measurements, such as cadence, stride length, ground contact time and balance, vertical oscillation and vertical ratio, are the key to understanding your form so you can bring your best on race day. These metrics are available with the addition of a compatible heart rate strap or the compact Running Dynamics Pod, which clips right onto your waistband. Also, take advantage of feature sets to help with cycling and even swim training. In the pool, Forerunner 645 will track your distance, pace, stroke count, and more.

Monitor Your Performance

The Forerunner 645 Sport Watch will help you monitor your training and recovery so you can better prepare for a race or training cycle. Training status is a performance monitoring tool that automatically evaluates your recent exercise history and performance indicators to let you know if you’re training productively, peaking, or overreaching. The anaerobic training effect metric opens a window of 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.

More Ways to Customize

Check out the free to use Connect IQ store, where you can add personality to Forerunner 645 Sport Watch by downloading apps, widgets, watch faces, and more. New apps are added every day, so you can keep tabs on when your Uber is arriving, turn on your lights at home with the SmartThings app, and even use the AccuWeather MinuteCast app to find out when the rain will start. With the Face It watch face app, choose any image from your photo library, make some tweaks, and set it as your watch’s face.

Stay Connected on the Run

The Forerunner 645 Sport Watch makes it easy to run without leaving important smart features behind. Once paired with your compatible smartphone, you’ll be able to receive and even respond to text messages and see social media updates, emails, and more right on your wrist. Find your phone, access music controls, and let friends LiveTrack your runs.

Share and Compete

Syncing your activities to Garmin Connect is for more than just storing your data. Garmin Connect is a thriving online community where people on the go can connect and compete by joining challenges, encourage each other’s successes, and even share their triumphs via social media. Garmin Connect is free and available on the web or on your smartphone with the Garmin Connect Mobile app.

Train Your Way

The Forerunner 645 Sport Watch lets you change things up with ease, thanks to built-in activity profiles for running (indoor/outdoor), cycling (indoor/outdoor), swimming (pool), elliptical, paddle sports, strength training, and many more. Create your own custom workouts, and download for free from our Garmin Connect online fitness community. Then review your past efforts on the app, or share them with family and friends for added motivation.

Love the Look

Designed for runners, the Forerunner 645 Sport Watch features a reliable five-button interface that lets you mark laps with a quick press. Feel free to take this watch outside in all kinds of weather. Not only is it safe for swimming and showering, its Garmin Chroma Display is easy to read – even in direct sunlight – and housed under chemically strengthened glass. When you want to change it up, swapping bands is fast and doesn’t require tools. And with up to 7 days of battery life in smartwatch mode and 14 hours in GPS mode, the Forerunner 645 is the running partner that can keep up with you.

Clock Features


GPS Time Sync

Automatic daylight saving time

Alarm clock



Sunrise/sunset times

Face It watch face creator




Garmin Elevate wrist heart rate monitor

Barometric altimeter





Daily Smart Features

Connectivity: 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)



Controls smartphone music

Find My Phone

Find My Watch

VIRB remote

Smartphone Compatibility: iPhone and Android

Compatible with Garmin Connect Mobile

Garmin Pay

Activity Tracking Features

Step counter

Move bar (displays on device after a period of inactivity; walk for a couple of minutes to reset it)

Auto goal (learns your activity level and assigns a daily step goal)

Sleep monitoring (monitors total sleep and periods of movement or restful sleep)

Calories burned

Floors climbed

Distance traveled

Intensity minutes


Move IQ

Fitness Age (in app)

Fitness Equipment / Gym

Preloaded Gym Activity Profiles: strength training, cardio training, elliptical training, stair stepping, floor climbing, indoor rowing, and yoga

Cardio workouts

Strength workouts

Automatic rep counting

Training, Planning, and Analysis Features

GPS speed and distance

Customizable data pages

Customizable activity profiles

Auto Pause

Interval training

Advanced workouts

Downloadable training plans

Auto Lap

Manual lap

Virtual Partner

Configurable lap alerts

V02 max

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)

Training Effect (aerobic)

Training Effect (anaerobic)

Customizable alerts

Audio prompts

Finish time

Race an Activity

Course guidance

Segments (Live, Garmin)

Strava features (Beacon, live segments)


Touch and/or button lock

Auto scroll

Activity history on watch

Heart Rate Features

HR zones

HR alerts

HR calories

% HR max


Recovery time

Auto max HR

HR Broadcast (broadcasts HR data over ANT+ to paired devices)

Running Features

Preloaded Run Profiles: running, treadmill running, indoor track

GPS-based distance, time, and pace

Running dynamics

Cadence (provides real-time number of steps per minute)

Performance condition (after running 6-20 minutes, compares your real-time condition to your average fitness level)

Run workouts

Race predictor

Foot pod capable

Outdoor Recreation Features

Preloaded Outdoor Recreation Profiles: skiing, snowboarding, XC skiing, stand up paddleboarding, rowing

Point-to-point navigation

Bread crumb trail in real time

Back to start


UltraTrac mode

Elevation profile

Distance to destination

Vertical speed

Total ascent/descent

GPS coordinates

Cycling Features

Preloaded Cycling Profiles: biking, indoor biking


Race an activity

Time/distance alerts (triggers alarm when you reach goal)

Compatible with Varia Vision (head-mounted display)

Compatible with Varia radar (rear-facing radar)

Compatible with Varia lights

Speed and Cadence Sensor Support (with sensor): yes (ANT+ and Bluetooth Smart)

Swimming Features

Preloaded Swim Profiles: pool swimming

Pool swim metrics (lengths, distance, pace, stroke count/rate, calories)

Stroke type detection (freestyle, backstroke, breaststroke, butterfly)

Swim efficiency (SWOLF)

Drill logging

Pool swim workouts

What’s in the box
Garmin Forerunner 645 Music Sport Watch – Slate

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1 review for Garmin Forerunner 645 Music Sport Watch – Slate

  1. Basson Engelbrecht

    Excellent watch

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