Tech Specs
Running is more than just exercise — it’s a performance. And Forerunner 645 has the tools to help you put on an outstanding show every time you lace up your shoes. Featuring contactless payments that let you buy what you need while on the go — plus advanced running dynamics and performance monitoring tools — this GPS running watch is the instrument you need to refine the performance.
Paying Made Easy
Always on the run? Feel free to leave your phone and wallet behind. Forerunner 645 features Garmin Pay contactless payment solution¹, 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.
Tune up Your Training
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 measurements², 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
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.
More Ways to Customize
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.
Stay Connected on the Run
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 respond6 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
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.
Love the Look
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.
Compatible with the following Garmin devices:
- Varia Rearview Radar
- Varia RTL510
- Varia Smart Bike Lights
- Varia UT800 Smart Headlight
- Varia Vision In-sight Display
- VIRB 360
- VIRB Ultra 30
In The Box
-
Manual & Warranty
Do you have an old GPS unit lying around? The GPS Nation Trade In and Up program is a great way to trade in your old and used GPS for credit towards a new GPS. The choice is entirely yours! We’ve made the process simple and streamlined. Follow these simple steps, and you will be on your way to receiving credit towards your brand new GPS!
1. Get a quote
To get your free quote, provide your GPS type, manufacturer, model, and condition. Within 24 hours, you will receive a quote for the trade-in value of your current product. The GPS trade-in/trade-up form is at the bottom of this page.
2. Ship your product(s) for trade
After accepting our offer, pack your product(s) safely and ship them to us using the pre-paid shipping label provided to you. We will provide a confirmation email when your trade-in arrives at our warehouse. You have 30 days from the date you complete your on-line trade to ship the product to GPS Nation.
3. Make your purchase
Once we receive your product at our warehouse and we validate the stated condition, we will send you a confirmation email. If you elect to receive credit towards a new GPS at gpsnation.com, your store credit will be issued, and you are free to make your purchase.
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Ask a Question
Tech Specs
Running is more than just exercise — it’s a performance. And Forerunner 645 has the tools to help you put on an outstanding show every time you lace up your shoes. Featuring contactless payments that let you buy what you need while on the go — plus advanced running dynamics and performance monitoring tools — this GPS running watch is the instrument you need to refine the performance.
Paying Made Easy
Always on the run? Feel free to leave your phone and wallet behind. Forerunner 645 features Garmin Pay contactless payment solution¹, 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.
Tune up Your Training
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 measurements², 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
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.
More Ways to Customize
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.
Stay Connected on the Run
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 respond6 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
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.
Love the Look
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.
Compatible with the following Garmin devices:
- Varia Rearview Radar
- Varia RTL510
- Varia Smart Bike Lights
- Varia UT800 Smart Headlight
- Varia Vision In-sight Display
- VIRB 360
- VIRB Ultra 30
In The Box
-
Manual & Warranty
Trade-In Program
Do you have an old GPS unit lying around? The GPS Nation Trade In and Up program is a great way to trade in your old and used GPS for credit towards a new GPS. The choice is entirely yours! We’ve made the process simple and streamlined. Follow these simple steps, and you will be on your way to receiving credit towards your brand new GPS!
1. Get a quote
To get your free quote, provide your GPS type, manufacturer, model, and condition. Within 24 hours, you will receive a quote for the trade-in value of your current product. The GPS trade-in/trade-up form is at the bottom of this page.
2. Ship your product(s) for trade
After accepting our offer, pack your product(s) safely and ship them to us using the pre-paid shipping label provided to you. We will provide a confirmation email when your trade-in arrives at our warehouse. You have 30 days from the date you complete your on-line trade to ship the product to GPS Nation.
3. Make your purchase
Once we receive your product at our warehouse and we validate the stated condition, we will send you a confirmation email. If you elect to receive credit towards a new GPS at gpsnation.com, your store credit will be issued, and you are free to make your purchase.
Overview
Running is more than just exercise — it’s a performance. And Forerunner 645 has the tools to help you put on an outstanding show every time you lace up your shoes. Featuring contactless payments that let you buy what you need while on the go — plus advanced running dynamics and performance monitoring tools — this GPS running watch is the instrument you need to refine the performance.
Paying Made Easy
Always on the run? Feel free to leave your phone and wallet behind. Forerunner 645 features Garmin Pay contactless payment solution¹, 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.
Tune up Your Training
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 measurements², 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
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.
More Ways to Customize
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.
Stay Connected on the Run
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 respond6 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
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.
Love the Look
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.
Compatible with the following Garmin devices:
- Varia Rearview Radar
- Varia RTL510
- Varia Smart Bike Lights
- Varia UT800 Smart Headlight
- Varia Vision In-sight Display
- VIRB 360
- VIRB Ultra 30