Polar M400

Polar M400

Polar M400 Features

  • Activity and Calories tracking
  • GPS
  • Walking Distance and Steps counting
  • Sleep Monitoring with Sleep Reports
  • Splash and Sweat Resistance (3 ATM)
  • Twentyfour Day Battery

Polar M400 Specs

Basic Info

Wear TypeWristband

Activity & Fitness Tracking

Sleep Analysis / Sleep Time
Heart Rate / Pulse
External HR Monitor
VO2 Max
Stairs / Floors
Exercise Tagging
Smart Coach
Goal Setting
Inactivity Alert

Additional Features

Watch / Clock
Alarm Clock
Music Playback
ReportsActivity, Sleep

Smartphone Remote Features

Caller ID
Music Control
Call Control
Camera Control
Find Phone


Duration24 days

GPS/HR mode: 8 hours

Battery TypeRechargeable Battery

Physical Specs

Water Resistance
IP Rating3 ATM
Weight57 grams
Dimensions38 x 50 x 11.5 mm


Display Technology
Display Sizen/a
Screen Resolution128 x 128 pixels
Color Display
Touch Screen


OS X / Mac
Windows Phone
Web Portal
Social Features



Sports and Fitness Activities

Best For:
  • All-Day Activity
  • Running
  • Walking

Polar M400 Review

The Polar M400 is an excellent smartwatch that keeps track of your activity and calories when working out. Users like the GPS function, sleep monitoring with sleep reports, and 24-hour day battery use. But is this all that they love or is there dislikes as well? Let us find out what the professionals had to say.

Pros / What Customers Like:

  • Athletes found the GPS tracking excellent and even the heart rate and daily fitness tracking fantastic.
  • Users love the lightweight design even with the GPS tracking onboard.
  • One of the most talked about feature is the slim and sleek design of the smartwatch compared to other devices available on the market. While it has a modern design they expected more than just the plastic feeling.
  • Joggers found the screen info bright enough to view outdoors while running and it has a backlight that is a big help.
  • The majority of sports users found the automated sleep tracking superb and sends inactivity alerts to your smartphone when paired via Bluetooth.
  • Sports professionals love loads of different activity profiles available and found the calorie counter to be very accurate.
  • Fitness users found the 15-minute fitness test outstanding as it gives you a VO2 max and running index score.
  • While the app on your phone is not the best, clients found the desktop Polar Flow site a bonus as it is bolstered with additional options to use. You can set up your sports profile and tell your watch when to turn on the HRM and GPS function.
  • Users found setting up the Polar M400 simple to do and use.
  • Professional trainers found the battery life of eight hours using GPS tracking and heart rate monitoring as advertised.

Cons / What Customers Don't Like:

  • Swimmers found the lack of underwater heart rate monitoring a big negative.
  • Hikers would have loved to see route navigation onboard.
  • Users found the need of using an extra chest belt with the watch to track their heart rate off-putting.


If you need a fitness smartwatch to keep track of time and your health the Polar M400 is an excellent buy. You can monitor your daily steps and sleep while using GPS tracking and get complex workout support. The wearable is well design and unbeatable at this size and price.

Compatible Applications

  • Polar Flow


Manufacturer Website: polar.com


Expert Reviews and Ratings

  • techradar.com • Expert Review by Mark Mayne

    An honestly priced, rugged and reliable running watch. It's not glamorous, but then nor is slogging through sleet at 7am. The Polar M400 won't let ... Full review

    4.5of 5.0
  • cnet.com • Expert Review by Dan Graziano

    The feature-packed and waterproof Polar M400 offers a good set of features for beginners and advanced runners a like. It also provides feedback on your ... Full review

    3.5of 5

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