Garmin Forerunner 645

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Garmin Forerunner 645: The Highlights

The ​Forerunner is a running watch family by Garmin.

The Forerunner 645 was released in 2019. The latest model in the family is the Garmin Forerunner 955.

Product comparison



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Garmin Forerunner 645
bestDealShow prices
priceBand
Price band
released
Released
Jul 2019
Jun 2022Dec 2014Jan 2022
expertReviewScore
Expert Review Score












Battery life
Battery life
168 hours
336 hours
480 hours
1220 hours
384 hours
Battery life – GPS mode
Battery life – GPS mode
12 hours
162 hours
49 hours
24 hours
105 hours
42 hours
Screen size
Screen size
30 mm
30 mm
33 mm
36 mm
20 mm
33 mm
Weight
Weight
42 g
58 g
53 g
85 g
43 g
76 g
Height
Height
43 mm
42 mm
47 mm
51 mm
40 mm
47 mm
Resolution
Resolution
240 x 240 px
240 x 240 px
260 x 260 px
205 x 148 px
156 x 156 px
416 x 416 px
Waterproof depth
Waterproof depth
50 m
100 m
50 m
50 m
100 m
100 m
Pixel density
Pixel density
283 ppi
282 ppi
282 ppi
276 ppi
452 ppi
Internal storage
Internal storage
32 GB
32 GB
8 GB
0 GB
16 GB
Health tracking features
Health tracking features
BMI trackingCalorie burn trackingPeriod notificationsSleep trackingTemperature tracking
BMI trackingCalorie burn trackingCalorie intake trackingPeriod notificationsSleep trackingTemperature trackingWater intake trackingWeight trackingBMI trackingCalorie burn trackingCalorie intake trackingPeriod notificationsSleep trackingTemperature trackingWater intake trackingWeight trackingCalorie burn trackingSleep trackingBMI trackingCalorie burn trackingCalorie intake trackingPeriod notificationsSleep trackingTemperature trackingWater intake trackingWeight trackingBMI trackingCalorie burn trackingCalorie intake trackingPeriod notificationsSleep trackingTemperature trackingWater intake trackingWeight tracking
Sensors
Sensors
AccelerometerBarometerBody temperature sensorCadence sensorCompassGalileoGPSGyroscopeHeart rate monitor
AccelerometerBarometerBlood oxygenation monitorBody temperature sensorCompassGPSGyroscopeHeart rate monitorAccelerometerBarometerBlood oxygenation monitorBody temperature sensorCompassGalileoGPSGyroscopeHeart rate monitor3D compassAccelerometerBarometerCompassGPSAccelerometerBarometerBlood oxygenation monitorBody temperature sensorCompassGalileoGPSGyroscopeHeart rate monitorMonitors perspirationAccelerometerBarometerBlood oxygenation monitorBody temperature sensorCompassGalileoGPSGyroscopeHeart rate monitorMonitors perspiration
Alerts
Alerts
Inactivity alertsVibrating alerts
Inactivity alertsIrregular heart rate warningsSilent alarmSmart alarmVibrating alertsInactivity alertsIrregular heart rate warningsSilent alarmVibrating alertsInactivity alertsInactivity alertsIrregular heart rate warningsSilent alarmVibrating alertsInactivity alertsIrregular heart rate warningsSilent alarmVibrating alerts
Supported peripherals
Supported peripherals
Compatible heart monitorCompatible smart scales
Compatible heart monitorCompatible smart scalesCompatible heart monitorCompatible smart scales
Compatible heart monitorCompatible smart scalesCompatible heart monitorCompatible smart scales
Screen features
Screen features
Force touch
Always-on displaySapphire glassTouch screenAlways-on displayDamage resistant glassTouch screenTouch screenAlways-on displayAlways-on displayDamage resistant glassOLED/AMOLED displayTouch screen
Battery features
Battery features
Battery level indicatorRechargeable battery
Battery level indicatorRechargeable batterySolar powerWireless chargingBattery level indicatorRechargeable batterySolar powerBattery level indicatorRechargeable batteryBattery level indicatorRechargeable batterySolar powerWireless chargingBattery level indicatorRechargeable batteryWireless charging
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Evolution of the ​Garmin Forerunner product family

Garmin Forerunner 645: 1 Expert video review

Garmin Forerunner 645 characteristics and specifications

Specificationsvs Average
Model
645
Released
Jul 2019
Measurements
Volume
24 cm³
Strap width
20 mm
Width
43 mm
Height
43 mm
Thickness
14 mm
Weight
42 g
Waterproofing
Waterproof depth
50 m
Screen
Pixel density
283 ppi
Resolution
240 x 240 px
Screen size
30 mm
Battery
Battery life – GPS mode
12 hours
Battery life
168 hours

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