Polar M400
GPS running watch

Polar M400 is a waterproof GPS running watch and daily fitness tracker. It can help you plan optimal training, break your records, and even find your way back from a run.

Buy now - $179.95
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Smart Notifications

Designed for life

Pair your phone with M400 and get alerts for incoming calls, received messages and push notifications from social media apps to your wrist and stay in the know wherever you are.

Don't miss a thing

See incoming calls and texts at a glance. Answer calls using your watch or decline them when training demands it.

Keep up to date

Read messages conveniently on the M400's display even when your phone is not at hand.

Be where you need to be

M400 alerts you about the appointments on your calendar and makes sure you're always on time.

Stay social

Receive push notifications from social media apps to your wrist and stay in the know wherever you are.

M400 features

Run beyond ordinary

  • Smart Coaching
  • Features
  • Specs

Training load

Shows you how your training affects your body and helps you compare the load of different sessions. Monitor your load continuously to recognize your personal limits and adjust training intensity and duration accordingly. Available on the Polar Flow web service. More ›

Recovery Status

Shows you the time necessary to recover before your next training session. Available on the Polar Flow web service. More ›

Fitness test

A five-minute test that measures aerobic fitness from your resting heart rate, heart rate variability and your background information. Complete the test regularly to see the progress you’re making. More ›

Running index

Shows how your running performance is developing. More ›

Training benefit

Delivers motivating feedback immediately after training and describes the effect of your workout. More ›

Smart calories

Lets you know exactly how many calories you’ve burned based on your weight, height, age, gender, your individual maximum heart rate (HRmax) and how hard you’re training. More ›

Activity Guide

Shows how active you’ve been during the day and gives practical guidance for reaching your daily activity goal. More ›

Activity Benefit

Gives feedback on your daily, weekly and monthly activity, showing how your active choices help you stay healthy. More ›

M400 whiteM400 blackM400 blueM400 pink

Advanced GPS

The M400’s built-in GPS keeps track of your pace, distance and altitude. With the “Back to start” feature you can safely explore new routes.

Activity tracking

The M400 tracks your steps, activity, sleep and calories 24/7, encouraging you to stay active every day.

Heart rate training

Heart rate training is one of the most effective training methods. Take advantage of it by using a Polar H7 heart rate sensor.

Running cadence from the wrist

Keep an eye on your running cadence to improve your running efficiency and avoid injuries.

Predict your event finish times

Based on your long-term progress, Running Index analysis predicts your event finish times for 5K, 10K, half marathon and marathon runs.

Polar Flow

Plan, sync and share your training using the exclusive Polar Flow online service and mobile application. All data is easily viewable.

Smart Notifications

Smart Notifications allow you to see notifications from your phone directly on the screen of your M400.

Individual targets

You can set your own individual training targets and follow your progress towards them using Polar Flow.

Speed and distance also indoors

Measure your speed and distance while running or walking indoors – all from the movement of your wrist.


Weight 56,6g
Thickness 11,5 mm
Display size 128 x 128 px high resolution display


Integrated GPS with AssistNow™ satellite prediction technology
Activity sensor
Manual and auto laps
Audio alerts
4 MB Flash memory
Rechargeable 190 mAh lithium polymer battery
Battery duration up to 8 hours of training time with GPS and Bluetooth Smart heart rate sensor


Standard micro USB cable for data sync with PC or Mac
Bluetooth Smart with mobile and sensors
Polar Flow web service compatibility with Mac OS X 10.6, OS X 10.7, OS X 10.8, or later, and PC Windows XP, Windows 7, Windows 8, or later
Polar Flow mobile app compatibility
Updatable software
UI languages English, Spanish, Portuguese, French, Danish, Dutch, Swedish, Norwegian, German, Italian, Finnish, Polish, Russian, Chinese, Japanese

Read the reviews

“Polar got it right here.”
– DC Rainmaker

The M400 has been positively received worldwide. Read what the experts are saying.

Made easy for you

Sync all your training details between M400 and the Polar Flow web service and app with Bluetooth Smart.

Made easy for you

After training get a quick visual overview of your training and analyze your achievements in the Polar Flow app.

Polar Ecosystem

Get connected

Polar has an entire ecosystem of excellent applications, services and accessories to help you get the most out of our products. Customize them to match your preferred look. Track your progress using the Polar Flow online service and app.

Polar Flow web service and app

Follow your daily progress and get guidance that helps you meet your goals. Learn how your daily habits can improve your wellbeing.

Polar Coach

Free online tool for your coach or personal trainer to easily follow your progress.

Sensor compatibility

For live, accurate heart rate, use the Polar H7 Bluetooth® Smart heart rate sensor. If you're interested in improving your running technique and performance, go with the Stride sensor Bluetooth® Smart.


Keep tabs on your nutrition by connecting with the world’s largest food, nutrition and calorie database (iOS only).

Buy Now

Take the next step

Buy from the official Polar webstore or find retailer

Buy Now - $179.95


Get support and the latest updates

Update your product to take advantage of the latest features and functionalities. Get support and user manuals.

Updates See all
2016.04.25Do you have your physical settings up to date?
2016.04.20Polar Team Pro – on the right track 24/7
2016.03.01A few tweaks to improve the Strava experience


Upgrade your performance

Upgrade your training computer to enhance your experience and achieve a more complete understanding of your performance.

M400 is rated 3.5843 out of 5 by 89.
Rated 4 out of 5 by from GPS I got this as a Christmas present and just love it. It is what I needed to get my butt moving. Only issue is I broke the wrist strap on the watch and can not find a place to buy a new one. What to do
Date published: 2016-04-25
Rated 5 out of 5 by from Love it I bought the m400 and I love it. It is the perfect training tool.
Date published: 2016-04-23
Rated 5 out of 5 by from Long time Polar customer I'm kind of a Polar junkie and really debated buying the M400 over a competitor brand because they had golf courses and most of my walking is done on the golf course. Actually very surprised at how much I like this fitness tracker now. You get great credit for your cross platform connectivity and ease of use. I use an iPhone and at the start it took several times to get the pairing to work but once it took, I've been off to the races. Great job Polar!
Date published: 2016-04-21
Rated 5 out of 5 by from Lovin' It Got a great deal on this watch and bought it because of the chest monitor for heart rate. I wanted more accuracy than wrist monitors as I am in my 40's and starting to get active again. I am extremely pleased with how well the GPS works on this watch, better than my Android. I went out to the desert to do some riding one weekend, came back and synced and next thing you know I could see everywhere I rode!! Mind you this area is in the middle of no where. I know GPS works via satellite but I was skeptical of such a small watch finding signal. I did notice that after last sync, GPS is taking longer to obtain signal. Hoping it is just a fluke and will be fixed to capture signal almost immediately as it was prior. The heart rate monitor does sync quickly and I did loosen it as it was too tight at fist. still have accurate results based against a stationary heart rate monitor. I really like the daily activity monitor as it motivates me to meet goals and try and catch up on days I was out due to illness of back pain. All in all a great fitness watch and thinking of upgrading to V800 to sync with GoPro when/if that comes about.
Date published: 2016-04-20
Rated 2 out of 5 by from M400 Features - Great Price - Bad Engineering I am adding this review for a 2nd time since it was removed. Not sure why as my review was fair and balanced. In my opinion the M400 is not engineered to previous Polar standards, especially the USB port. Nor does the M400 USB port design match that of my other devices. As I stated previously, I have been a happy Polar customer for 12 plus years having used the S210, SX625/725, RC8000CX, Polar Beat, Polar Balance. So I have demonstrated my commitment. Unless something have changed from September 2015 when I purchased the M400, the issues customers are describing regarding charging, etc is because the USB port is not "encased" or "surrounded" by another material to form a single connective piece. All other Micro USB devices encase or surround the individual PINs to provide protection and to give the connector something to "connect to". The M400 is simply a row of PINs that "conforms" to the "shape" of a USB connector. Which means what? Each PIN is susceptible to water, salt, and the damage that could result from multiple charges. In my opinion, it is this engineering flaw and not the cover that has contributed to everyone's issues. And I challenge Polar to step up and suggest otherwise.
Date published: 2016-04-19
Rated 4 out of 5 by from I want to give this five stars, but... I purchased the M400 a few weeks ago. I really love the features, the HRM isn't uncomfortable like I was worried it would be, much more accurate than my previous tracker, the feedback is great, etc. I could go on about everything, but the syncing. Wireless sync to Polar Flow doesn't work for me and I really wish it did :( I finally strayed from my previous tracker, which automatically synced, and figured I could live with pressing a button to sync, but even that doesn't work. To sync my info, I have to take it off and physically plug it in to a computer. It's not that I never take it off. It's more of the convenience factor. I previously read a review from someone whose car connects to his phone via Bluetooth and that that may have been what was causing connection issues. My car connects automatically too, so I'm not sure if that's what it is? Either way, I'm not going to go through forgetting the device on my phone and re-pairing it every time I want to sync because that's just annoying. Also, Polar should really consider manufacturing these devices in different sizes or advertising better. I purchased the blue one and it's huge. The band wraps all the way around to within an inch of the screen. Nowhere is it advertised (that I can find) that the pink one has a shorter band. If it would've been, I'd have purchased it, as I have pretty small wrists (I'm not opposed to pink, but I'm sure there are people who are. Why is this the only option?). I only ended up finding this out (after I ordered/used mine) from a 3rd party website review and got confirmation from Polar after I asked a chat representative.
Date published: 2016-04-19
Rated 4 out of 5 by from Simple and Usefull I had the M400 since the start of the new year and it does what I want a sport watch to do. It's not much bigger than most sports watches but it has a gps, so I can just go run without changing watches or carrying a phone. I usually wear my watch 24/7 and has held up well so far. It's also nice to have some of the smart features enabled so I don't always need my phone on me around the house.
Date published: 2016-04-18
Rated 5 out of 5 by from 1st anniversary - still getting better I bought my M400 in March 2015. I have never had issues with heart rate, syncing, charging or finding GPS. All of the sport profiles and display options give me everything I need. How fun is it to relive a ski day and see all of your runs and how fast you skied! I also use it for the normal hiking, biking and group exercise (among others). The firmware updates and polar flow web updates just keep making it more useful. I particularly like the training load and recovery status features. I added a Polar Loop 2 a few months ago to wear for daily activity tracking - the M400 is a little too big to wear to the office, etc. The products sync perfectly across the platform. I like the fact Polar is activity driven instead of step driven - otherwise, it's really just an expensive pedometer.
Date published: 2016-04-16
  • 2016-04-30T07:00CST
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