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  • Built-in GPS tracks pace, distance and altitude of your workouts, and monitors your daily activity including steps and calories
  • Plan, sync and share your training with the Polar Flow mobile app and web service; set personal targets and track progress right from your wrist
  • Train at the right intensity with personalized heart rate zones and monitor your heart in real time during exercise
  • Quick workout overviews are available immediately after each session; for more detailed feedback, go to the Polar Personal Trainer website for further in-depth analysis
  • Fitness Test delivers actual fitness progress, letting you assess your progress and make adjustments as necessary; daily running index data helps you improve stride efficiency
  • OwnCal calculates calorie burn during training sessions based on your weight, height, age, gender and your individual heart rate data for exceptional accuracy
  • Activity Guide delivers practical recommendations and durations for meeting fitness goals, so you can choose how to maximize your schedule and stay on track
  • Activity Benefit tracks all your active choices during the day and provides daily rewards for goals reached, motivation for pending goals and monthly feedback summaries
  • Waterproof construction lets you train in any weather
  • Includes M400 watch, Polar H7 heart rate sensor/band and USB charging cable; heart rate monitor enables heart rate target training, Fitness Test and Activity Benefit features


View all Polar GPS Sports Watches

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Best Use Fitness
GPS/Satellite Detectable Yes
Tracks Steps Yes
Tracks Calories Burned Yes
Sleep Tracking Yes
HRM Included/Integrated Yes
Heart Rate Sensor Type Chest Strap
Average Heart Rate Yes
Heart Rate Target Zone(s) Yes
Water-Resistant Depth 30 meters
Altimeter Satellite-based
Alarm Yes
Time Display Yes
Illumination Backlight
Average Battery Life Up to 8h training time (when both GPS and HR in use), 24 days in time mode with daily activity monitoring
Compatible Fitness Accessories Heart Rate Monitor
Included Fitness Accessories Heart Rate Monitor
Gender Unisex
Rated 4 out of 5 by from Love it and use it daily to help me achieve my goals. The Good: -Waterproof (great for swimming and dont have to take it off to shower) - Tracker measures your body movement towards your daily goal, not just steps - Easy to read face even in direct sunlight - Sturdy band that adjust to almost any size wrist - No it can be a smartwatch as well with update - GPS tracker is on the money! - Easy to sync to mobile devices The Bad: - Placement of the USB port (have to fumble around to get to) - NO vibrating alarm. The audible alarm is WAY too low to hear (major diffencency) - No special notifications on incoming smartwatch features I would rate it GREAT if it wasn't for those few bad (but livable) issues
Date published: 2015-06-14
Rated 5 out of 5 by from LOVE IT!! I've tried many running watches over the past few years including Garmin, Tom Tom, Timex, and Nike. This by far is my favorite watch. Its masculine, fits great, and has many features. The screen is my favorite part of the watch though. I can have up to 4 lines of data on one screen. you can customize the watch via your computer, sync it to the watch and boom done.. I didn't get the heart rate package because I have several monitors, also because it will connect to any "Bluetooth" monitor on the market. So $180 for a watch that compares to others in the 250 and up range is pretty nice. PLUS Polar has outstanding quality in my opinion, and this feels VERY premium. CONS: The GPS time... it can take a bit longer than I want to find a signal but its not that bad.
Date published: 2015-01-02
Rated 5 out of 5 by from The perfect all in one device. This watch is first in its class and perfect for anyone that doesn't want to have multiple devices to track their workouts or activity. The GPS feature works great and the activity monitor. Having the heart rate monitor makes it even better. Its priced cheaper than the some of the other GPS watches, but has more features which makes it a great buy. Nike's watch is about $30 cheaper but doesn't have nearly the amount features. Garmin and TomTom's watches are $70 more with less features. It wasn't a hard decision to purchase this watch.
Date published: 2014-11-17
Rated 4 out of 5 by from Mostly great I've owned my M400 for 2 weeks. I'm happy with almost everything about it. I wear it all day and all night and like the type of feedback it gives on activity, sleep and training. I'm small, so it's a little big on my wrist but I'm not really worried about that. Love how it guides me through pre-programmed training targets. My biggest gripe is the syncing between the watch and mobile device via Bluetooth. There is definitely a glitch somewhere. Just being able to pair and connect is hit or miss. When I successfully sync, then it screws up the data - in some cases data already downloaded. Syncing via USB cable works fine so I will probably just use that. A little disappointing. Still, can't beat the price given the number of working features.
Date published: 2015-01-29
Rated 5 out of 5 by from M400 without built in heart rate monitor = WIN! I've had a Nike GPS watch for the past two years and recently got a Garmin fitness tracker to keep an eye on my daily activity....ended up not liking to have to wear two devices. I got my M400 about a week and a half ago and have used it on a run and several gym workouts and I really am impressed. It's very comfortable and easy to use. The activity tracking along side with the GPS is great. I got the model without the built in heart rate monitor because I'm used to wearing a strap; the ability to see zones is really nice. I think it looks great as well (got black)! Can't wait for the mobile app for Google Play to be up and running, being able to sync via Bluetooth with mobile would be icing on the cake! Also, I love the strap and how it closes. I really have no complaints....just anxious about the mobile app.
Date published: 2014-12-03
Rated 4 out of 5 by from Excellent start but looking forward to more I have been very impressed so far but would love to see you continue to push this device to the limit. Enhanced bluetooth integration would be great. The mobile app needs work and seems dated compared to the online site. Unless I am mistaken the sync app on the Mac only syncs by USB. Since most competitors offer bluetooth sync from Mac, I would expect at least the same to be available. This would allow syncing on mobile and Mac to be done without removing the device. Also there are minor quality control issues, such as the band edge being rough and not smooth; almost as if it was cut with scissors. While not possible with this version, vibration is standard in the industry and audible tones are not useful when running or training with headphones. Minor gripes for an amazing device. Please keep pushing the limit on this. Remember today's great is tomorrow's average. I would love to see where you take it. Cheers and God bless!
Date published: 2015-02-24
Rated 5 out of 5 by from Awesome fitness watch! I can't stress enough how awesome this watch is. All the features it has and the polar flow website gave really helped me to stay on track with workouts. The back to start feature is really useful for those days when you just want to go on a free run and don't want to be worried about getting lost and not finding your way back home. I like that it also tracks my activity throughout the day. I've owned other fitness bands from other companies but none of those come close to this. If you're one the fence about this watch, get it.
Date published: 2015-01-10
Rated 5 out of 5 by from Polar has really outdone itself I bought this watch because I wanted a greater amount of data from my workouts, and especially for those backcountry ski and hiking days. I am so incredibly impressed with how well Polar delivers. I am writing this review on Thursday, I got the watch on Tuesday. Right out of the box everything worked the way it should. Easy to pair to your computer, phone, and set up portal online. Tracks sleep pretty well and steps too (though I am convinced that if you walk like I do - with heavy steps - that it adds about 2x times as many). I took this backcountry skiing today along one of my favorite routes. Took a minute to find the signal, and didn't have a single problem thereafter. once you sync the data to the app after you are done, it then syncs online and you can view a plethora of data. One of my favorite features has to be the training notes section and the ability to name a favorite route - for comparison at a later time to the same workout. I could go on forever about this watch, but I would highly recommend it. Unbelievable that for less than $250 (inc tax) you can get a watch that does all this and is not that much larger than about 90% of the other polar HRMs I have owned. Would recommend to anyone looking for an activity tracker, GPS HRM, and who like to analyze workout data for future gains. You won't be disappointed.
Date published: 2015-01-15
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Will this watch fit my 5 1/8" wrist and will the band adjust to 33"?

Asked by: PJinNY
The watch band fits wrists as small as 5 1/2 inches. The heart rate strap adjusts down to 24 inches.
Answered by: REIservice
Date published: 2016-09-15

Can this watch be used while swimming? It says water resistant, but would it be a good watch for triathlon training?

Asked by: KaraColorado
You could use the M400 while swimming and there is a swimming mode however there is no lap/distance tracking in either indoor or outdoor swimming. The M400 will also not capture heart rate data underwater. The Polar V800 would be a better choice for triathlon training.
Answered by: REIservice
Date published: 2016-09-30

If you like the watch but not the HR strap, can you return the monitor for the price difference of the package vs just the watch?

Asked by: acc95
We do not offer partial refunds and are only able to return complete products.
Answered by: REIservice
Date published: 2016-08-01

In the Specs, what does "user replaceable Batter = NO" mean?   Does the unit have to be sent in? if so what is typical cost and turnaround time? 

Asked by: Rave On
The battery on the Polar M400 is rechargeable so you will not have to replace it. You should expect about 8 hours of training time or 24 hours of time mode from a fully charged battery.
Answered by: REIservice
Date published: 2015-09-20

Can I customize the display to show what is seen on each line?

Asked by: Crestas
You can customize the data fields on the display of this watch.
Answered by: REIservice
Date published: 2016-10-11

What is the size of the face of the Polar M400? What store in the metropolitan Portland Oregon area has one I can try on?

Asked by: Denny
The face of the M400 will measure 2 x 1.5 x .5 inches. The Clackamas, Hillsboro and Portland stores are showing stock as of 2/24/2015.
Answered by: REIservice
Date published: 2017-01-27
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