1. Easily download up to 500 songs to your watch, and connect with Bluetooth headphones (sold separately) for phone-free listening
2. Syncs music from select streaming services for offline listening
3. Garmin Pay contact-less payment solution lets you make convenient payments with your watch, so you can leave your cash and cards at home (Coming Soon!)
4. Provides advanced running dynamics, including ground contact time balance, stride length, vertical ratio and more
5. Uses wrist-based heart rate to offer performance monitoring features, including evaluating your current training status
6. Connected features include smart notifications, automatic uploads to Garmin Connect and the ability for others to track your runs with the LiveTrack feature
7. Customize with free watch faces, apps and more from our Connect IQ store
8. Battery life: up to 7 days in smartwatch mode; 14 hours in GPS mode

We’re making it easier to get the data you need to improve your form. Let Forerunner 645 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.

Just how effective is your current training plan? Forerunner 645 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.

Check out our Connect IQ store, where you can add personality to Forerunner 645 by downloading apps, widgets, watch faces and more. It’s easy and — even better — it’s free. 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.

Forerunner 645 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.

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.

Your routine is anything but routine. Forerunner 645 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.

Designed for runners, Forerunner 645 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 12 hours in GPS mode, Forerunner 645 is the running partner that can keep up with you.

Always on the run? Feel free to leave your phone and wallet behind. Forerunner 645 features 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. A bottle of water here, a bite to eat there — just pay, and keep on moving.

- Lens Material: chemically strengthened glass
- Bezel Material: stainless steel
- Quick Release Bands: yes (20 mm, Industry standard)
- Strap material: silicone
- Size: 42.5 x 42.5 x 13.5 mm
- Weight: 41.8 g
- 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
- Color display: Yes
- Battery life: Smartwatch Mode: Up to 7 days
- GPS mode: Up to 12 hours
- Memory/History: 200 hours of activity data
- Time/date
- GPS Time Sync
- Automatic daylight saving time
- Alarm clock
- Timer
- Stopwatch
- Sunrise/sunset times
- Face It™ watch face creator
- Garmin Elevate™ wrist heart rate monitor
- Barometric altimeter
- Compass
- Gyroscope
- Accelerometer
- Thermometer
- 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)
- Calendar
- Weather
- Controls smartphone music
- Find My Phone
- Find My Watch
- VIRB® remote
- Smartphone compatibility - iPhone and Android
- Compatible with Garmin Connect Mobile
- Garmin Pay
- 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
- TrueUp™
- Move IQ
- Fitness Age
- 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
- 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)
- LiveTrack
- Touch and/or button lock
- Auto scroll
- Activity history on watch
- HR zones
- HR alerts
- HR calories
- % HR max
- % HRR
- Recovery time
- Auto max HR
- HR Broadcast (broadcasts HR data over ANT+ to paired devices)
- Preloaded run profiles
- 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
- 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
- TracBack
- UltraTrac mode
- Elevation profile
- Distance to destination
- Vertical speed
- Total ascent/descent
- GPS coordinates
- Preloaded cycling profiles - Biking, Indoor Biking
- Courses
- 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) - ANT+ and Bluetooth Smart
- 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