Garmin Forerunner 645

Garmin Forerunner 645

Garmin Forerunner 645 review: specs and price

Garmin Forerunner 645

Why is Garmin Forerunner 645 better than the average?

  • Weight
  • Resolution
    240 x 240pxvs26313.04px
  • Thickness
  • Height
  • Pixel density
  • Screen size
  • Width of band
  • Width

Top specs and features


1.Is dustproof and water resistant
Garmin Forerunner 645

Dustproof/water resistant at depth equal to or greater than 1 meter.

2.sweat resistant
Garmin Forerunner 645

Resistance to sweat makes it ideal for use while doing sports.

3.Has a display
Garmin Forerunner 645

The device has an electronic display to present information to the user.


240 x 240px


Suunto 9 Baro

300 x 320px




Polar RCX3 GPS


6.waterproofing maximum depth


These devices will not experience water damage, e.g. in the shower. Devices which can withstand more water pressure are better for swimming or diving.


Casio GWA1000FC-2A



1.has GPS
Garmin Forerunner 645

GPS enables global positioning, useful in map, geo-tagging or navigation apps.

2.Has a heart rate monitor
Garmin Forerunner 645

A heart rate monitor can help show your fitness levels, enabling you to calculate a suitable intensity of exercise.

3.Has a barometer
Garmin Forerunner 645

This measures barometric air pressure. It can predict weather changes, for example a sudden drop in air pressure could mean a storm is coming. When calibrated correctly it can be used to determine altitude, which helps GPS devices to lock on quicker and with greater accuracy.

4.has an accelerometer
Garmin Forerunner 645

An accelerometer is a sensor used to measure the linear acceleration of a device. A common application is detecting when a device changes between vertical and horizontal positions.

5.has a compass
Garmin Forerunner 645

A compass is useful in games, map and navigation software.

6.Has a 3D compass
Garmin Forerunner 645

3D compass is a compass that will show accurate readings also when the compass is tilted. Therefore you don’t need to keep the compass on level ground to get steady readings.

For example

Garmin Fenix 5X

Activity tracking

1.Tracks distance
Garmin Forerunner 645

It tracks how far you travel.

2.Provides activity reports
Garmin Forerunner 645

Your activity data is analysed to give you reports, available to view through the app or website. This allows you to see how active you have been and to help you make improvements.

3.Has a route tracker
Garmin Forerunner 645

With a route tracker you can add your route onto a map. It is helpful if you plan to do the same route again, or want to share it with your community.

4.Measures pace
Garmin Forerunner 645

Measuring pace shows how much time it takes to travel one kilometer or one mile. For example, in running, a 4 minute kilometer would be a very good pace.

5.Has goal setting
Garmin Forerunner 645

Allows you to set your own goals, such as reaching 15,000 steps in a single day.

6.Counts how many calories you have burnt
Garmin Forerunner 645

This is useful if you are on a strict training diet or if you are trying to lose weight. It can also help to boost your motivation.


1.Syncs wirelessly
Garmin Forerunner 645

The device syncs all of your data wirelessly, without the need for cables.

2.Has Bluetooth
Garmin Forerunner 645

Bluetooth is a wireless technology that allows you to easily transfer data between different devices, such as smartphones, tablets and computers.

3.Is compatible with Android
Garmin Forerunner 645

It is compatible with a range of Android devices such as smartphones and tablets.

4.Is compatible with iOS
Garmin Forerunner 645

It is compatible with a range of iOS devices such as iPhones, iPads and the iPod Touch.

5.Supports ANT+
Garmin Forerunner 645

ANT+ is a wireless protocol similar to Bluetooth Smart, and is very power efficient. It is mainly used for fitness monitoring devices such as heart rate monitors and cadence sensors to connect to other devices, eg. sports watches, smartphones and cycling computers.

6.Has 802.11n WiFi connection
Garmin Forerunner 645

802.11n is a wireless standard released in 2009. It has faster transfer rates and improved security compared to its predecessors - a, b and g.


1.has a battery level indicator
Garmin Forerunner 645

An indicator shows you when the device has low battery.

2.battery life with GPS on


There is less chance that you will run out of battery during an adventure.


Suunto Ambit3 Peak Sapphire (HR)


3.battery life

7 days

With a longer battery life, you don’t have to worry about charging the device as often.


Tech4o Traileader Jet

730 days

4.has a rechargeable battery
Garmin Forerunner 645

The battery can be recharged and used over again.

5.Alerts you to low phone battery
Garmin Forerunner 645

When your paired smartphone is running low on battery, the smartwatch will notify you.

For example

Garmin Forerunner 645 Music

6.has a removable battery
Garmin Forerunner 645

The battery is removable and can be replaced by the user if broken.

For example

Magellan Echo Fit


1.Has vibrating alerts
Garmin Forerunner 645

Vibrating alerts have a variety of uses, such as interval training.

2.Has silent alarm
Garmin Forerunner 645

The device can wake you using vibration, so as not to disturb anyone else sleeping in the room.

For example

Garmin Forerunner 645 Music

3.Has achievements
Garmin Forerunner 645

You are awarded achievements for reaching goals, helping to encourage you and keep you motivated.

4.Can upload maps
Garmin Forerunner 645

You can upload different maps to your device. It is handy for people who like to explore new places.

For example

Suunto 9 Baro

5.Acquires GPS faster
Garmin Forerunner 645

It can periodically download data on the future position of GPS satellites. This enables it to lock on much faster, so you don’t have to wait around to get a GPS fix.

For example

TomTom Spark 3

6.Has inactivity alerts
Garmin Forerunner 645

The device detects when you have been idle for too long, and alerts you to encourage you to stay active.

For example

Garmin Forerunner 645 Music


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