Product Comparison: Garmin Forerunner 620 vs Polar M400

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General Specifications
About the Product
The 620 is the first GPS running watch that provides feedback on your running form by reporting multiple metrics. When used with the HRM-Run monitor¹, the 620 reports your cadence, vertical oscillation and ground contact time. These metrics are called running dynamics, and they affect your running economy.
Developed for runners who want a comfortable and durable running watch with sporty design and advanced GPS and training features. Track and record running as well as your other exercise, and monitor your performance accurately. Connect with the Polar Flow mobile app and stay active and motivated.
Forerunner 620
Key Specs
Display Type
Monochrome LCD
Monochrome LCD
Display Size
1.0" x 1.0" (180 x 180 pixels)
0.94" x 0.94" (128 x 128 pixels)
Built-In GPS
Other Sensors
Optical heart rate monitor
What customers say about "Key Specs"
Garmin Forerunner 620 White/Orange
  • The touch screen really works. It's more of a tap than a touch. You rap the glass with your nail. That's easy to do when you're running.
  • Good GPS, nice display, nice colors, very recommended!
  • GPS so uccurate! My previous devise was worse.
  • The graphc display for the watch as shown here and on Garmin's web site is extremely inaccurate. In reality the colors are super muted and the background is very gray green.
  • I'm very dissapointed with GPS, works bad!
Polar M400 GPS Smart Sports Watch
  • The GPS work perfectly & quickly & accurately 100% of the time but this device has a large, easy-to-understand, perfectly user-friendly display!!
  • Perfect GPS, very occurate, very stable!
  • I love that display, convinient size and good colors!
  • GPS is a little finicky at times, takes a while to lock into the signal and controls could be better.
  • I always have a GPS finding issues, so frustrated!
Size & Weight
1.8 in.
2.2 in.
1.8 in.
1.96 in.
0.5 in.
0.47 in.
1.5 oz.
1.7 oz.
Tracking Features
Calories burned
Pace, Distance
Vibration Alerts
Clock Features
Time/date, Alarm
Time/date, Alarm
200 hours of activity data
30 h training with GPS and heart rate depending on your language settings
What customers say about "Functionality"
Garmin Forerunner 620 White/Orange
  • Easy to see my numbers on it during my race, light and alerts me what I need.
  • The vibration is so attractive to the body, I love this watch
  • Clock featurer are clearly to see, very comfortable for running!
  • Considering this is a running watch, I hate how "Indoor Running" isn't an automatic activity profile to select from.
  • It would be better if alerts be more loudly.
Polar M400 GPS Smart Sports Watch
  • It is pretty cool. It gives you all kinds of info with maps, graphs, and charts.
  • This device records a ton of data and displays all of that data on the screen for you, and it even has a daily diary right on the screen.
  • The best part may be that I can set two interval timers to count down and alarm in continuous cycles, so I don't have to keep stopping and starting them during my run.
  • Like everyone else, I find the beep alerts hard to hear and wish it would vibrate, but I'm glancing down often enough that it isn't much of a problem.
  • The thing that I don't like is that it doesn't vibrate and it's kind of hard to hear it beep when Im running.
USB / Bluetooth
USB / Bluetooth
IOS, Android
Android, IOS
Water rating - 5 ATM
Water rating - 5 ATM
Wristband Material
Battery Type
Rechargeable lithium-ion
Rechargeable 240 mAh lithium polymer
Battery Life
Up to 6 weeks in watch mode; up to 10 hours in training mode
Battery duration up to 8 hours of training time with GPS and optical heart rate. Daily training session, continuous heart rate tracking and notifications: 5 days No training sessions, no notifications, continuous heart rate tracking: 14 days
Customizable data pages, Auto Pause®, Interval Training, Advanced workouts, Auto Lap®, V02 max, Virtual Partner, Virtual Pacer™, Auto scroll, Personal records, Race predictor, Recovery advisor, Garmin Connect™ compatible
Running Program, Running Index, Continuous Heart Rate, Smart Calories, Sleep Plus, Training Load, Recovery Status
What customers say about "Features"
Garmin Forerunner 620 White/Orange
  • My favorite features is the VO2. Just try it and you will say same!
  • The battery does not discharge for a long time, even if actively used.
  • Main advantage of this device is battery! I'm so pleased!
  • After 4 days(3 runs) it stopped working reliably and I have to fiddle with the magnetic lock for upwards of an hour to get it to charge or it will look like it's charging but actually will be discharging.
  • I didn’t use the watch for long, the battery started to run out quickly!
Polar M400 GPS Smart Sports Watch
  • It has full support for the Mac computer, so you can plug it into your Mac, and it will sync to the Polar website.
  • Battery life is fantastic. I have never had trouble charging/syncing this watch.
  • I've been happy with battery life so far, it will generally last for a week of workouts no problem.
  • Battery life is pretty good, good purchase!
  • I have one complaint it's that the battery is only lasting 2-3 days.
Warranty / Certifications
Manufacturer Warranty
1 year(s)
2 year(s)
Other Information

Price History

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