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 ›

Running Program

Train for a running event with a personal and adaptive training plan in Polar Flow. Choose from four different targets, 5K, 10K, half marathon and marathon, and get a training plan that fits you and your goals. More ›

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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
2016.06.07Polar M400 firmware update
2016.05.11Polar M400 software update with Strava pause time indicator
2016.05.04The Polar Running Program is here
Product Support


Upgrade your performance

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

M400 is rated 3.4646 out of 5 by 99.
Rated 2 out of 5 by from Disappointed Bought M400 with H7 sensor. Seems accurate but synchronization with app is shaky at best. The very first sync put my results 4 months into the future because the software didn't account for the date format on the watch. The date was correctly set in European format, but the software assumed U.S. format during the sync. After resetting the date, synchronization with Samsung Note 5 mostly worked for about 15 days, storing both recorded workouts and daily activity. I say "mostly worked" because there are 5 days out of the last 15 in my log when I did not even wear the watch, but somehow still managed to burn 1568 or 1569 kcal (always one of those two amounts). Recently, any attempt to sync the M400 with my Samsung Note 5 results in a "sync failed". The recorded workouts are still uploaded, but they no longer count towards daily activity. The daily activity view on the mobile app now shows nothing even for days when I've worn the watch and the activity progress bar has exceeded my quota. I followed the troubleshooting recommendations on the Polar support site, i.e. unpaired and re-paired the M400 with phone, power cycled phone, etc.. but still not synchronizing correctly. I previously owned a Polar monitor which had no capability to connect to a computer, but gave me many years of good service and accurate data. I really wanted to like the M400 but I am now regretting the purchase.
Date published: 2016-06-26
Rated 4 out of 5 by from First timer to M400 I purchased the M400 and bought the chest strap separate, to keep track of my workouts (circuit training, running, trail running and OCR races). being my first sports tracking watch, I have enjoyed it and found it beneficial to keep track of HR zones and pace, cadence, elevation! one bad thing is charging in back and syncin with polar flow app in iphone. but besides that as of now really like the watch. wish they would make screen color with better display graphics instead of black and white, but not a decision breaker
Date published: 2016-06-21
Rated 1 out of 5 by from Terrible watch My watch is again unable to charge or synch. The problem is that the charging port is located on the back of the watch next to sweaty skin. Unless this design is changed, do not buy it. When it is working, the watch is great. I'm going to send it back again but am already looking at buying a different brand, which really stinks because I will lose all my training data.
Date published: 2016-06-13
Rated 1 out of 5 by from Do Not Waste Your Money I am currently on my second m400. Both have only last a little over a month, then they stop charging. It is so frustrating because I have always used Polar products without any problems until now. I have cleaned the back and have followed all instructions.
Date published: 2016-06-05
Rated 3 out of 5 by from for the price of the watch you think it would come i bought my first fitness watch after everyone raving about it. i sorta see why but at the same time for how much it cost i thought it came with a heart rate moniter. i have the m400. debating on returning it or what not.
Date published: 2016-05-17
Rated 3 out of 5 by from I love this watch, but it does have a few bugs. I’ve had mine for over a year now and wear it mostly just for workouts 6-7 hrs/week. The notifications feature doesn’t work with my Samsung Galaxy Core Prime. It continuously loses the Bluetooth connection, so it’s completely unreliable. This was a new feature added after I bought the watch, so I can’t really complain, but if you buy one expecting this to work you’ll be disappointed. Also, the USB cable doesn’t sync with my computer without a ton of fiddling. This has gotten worse the longer I’ve owned it and at this point may not work at all. Fortunately, it always charges fine and I can use Bluetooth to sync with my phone, so until I need a firmware update I haven’t lost any significant functionality. Other than that, the feature set and usability are great. I also appreciate that Polar is continuing to update the product through firmware updates.
Date published: 2016-05-16
Rated 1 out of 5 by from Doesn't charge. Doesn't sync. I got this for Christmas and loved it for the first month or so. Then I kept having difficulties getting it to sync and charge. I sent it back to Polar ($7 shipping and a half hour at the Post Office). I got it back today and it's still not working. In fact it wasn't even charged. I guess all they did was pull the USD cover off and send it back. Thanks Polar. Not pleased.
Date published: 2016-05-12
Rated 4 out of 5 by from Been very happy with this. Bought this after researching GPS watches and activity monitors endlessly. When I worked out what I needed versus what I wanted, turns out the M400 gave me all of what I needed and most of what I wanted wanted. I've had this watch for over a year now, and it only comes off my wrist to charge or strap to the handlebars for biking. I've found the GPS to be accurate, and if updated regularly, the GPS locating happens quickly. The HR strap is comfortable and I have had zero issues with it. Overall, I am really happy with my purchase and has held up well in the first year. Whenever I had a question or concern, Polar has always responded quickly via phone or Twitter. Only complaint is that it doesn't have a stop watch, that I can figure out.
Date published: 2016-05-09
  • 2016-06-30T07:30CST
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