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Fitbit Ionic vs Garmin Forerunner 645

    Fitbit Ionic Fitness Watch
    Fitbit Ionic
      Garmin Forerunner 645 Fitness Watch
      Garmin Forerunner 645
      Available colors
      Editiorial reviews
      16
      3.7 out of 5
      7 user ratings
      5 stars
      		0 %
      4 stars
      		85 %
      3 stars
      		14 %
      2 stars
      		0 %
      1 stars
      		0 %
      Read editorial reviews
      10
      3.8 out of 5
      6 user ratings
      5 stars
      		16 %
      4 stars
      		50 %
      3 stars
      		33 %
      2 stars
      		0 %
      1 stars
      		0 %
      Read editorial reviews
      User rating
      47
      4.1 out of 5
      47 user ratings
      5 stars
      		36 %
      4 stars
      		42 %
      3 stars
      		21 %
      2 stars
      		0 %
      1 stars
      		0 %
      53
      4.0 out of 5
      53 user ratings
      5 stars
      		35 %
      4 stars
      		37 %
      3 stars
      		15 %
      2 stars
      		9 %
      1 stars
      		1 %

      Video Comparisons (1)

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      Full Comparison

      Units:

      Display

      Fitbit IonicFitbit Ionic
      Garmin Forerunner 645Garmin Forerunner 645
      Touchscreenyesno
      Colour screenyesyes

      Dimensions

      Fitbit IonicFitbit Ionic
      Garmin Forerunner 645Garmin Forerunner 645
      Gender
      • Men's
      • Women's
      • Men's
      • Women's
      Width1.5 in1.67 in
      Depth1.5 in1.67 in
      Weight1.76 oz1.47 oz
      Thickness0.47 in0.53 in

      Design

      Fitbit IonicFitbit Ionic
      Garmin Forerunner 645Garmin Forerunner 645
      Colour of product
      • Black
      • Blue
      • Grey
      • Orange
      • Silver
      • White
      • Yellow
      • Beige
      • Black,Stainless steel
      • Grey
      • Purple
      Protection featuresWater resistantWater resistant
      Waterproof depth505

      Features

      Fitbit IonicFitbit Ionic
      Garmin Forerunner 645Garmin Forerunner 645
      Heart Rate MonitorBuilt-inBuilt-in
      Calorie counteryesyes
      Alarmyesyes
      Altimeteryesyes
      Date displayyesyes
      Pedometeryesyes
      Sleep readingyesyes
      Timeryesyes
      Vibration alarmyesyes

      Connectivity

      Fitbit IonicFitbit Ionic
      Garmin Forerunner 645Garmin Forerunner 645
      Bluetoothyesyes
      GLONASSyesyes
      GPSyesyes

      Power

      Fitbit IonicFitbit Ionic
      Garmin Forerunner 645Garmin Forerunner 645
      Battery typeLi-polymerBuilt-in
      Battery life (running)10.0 h168.0 h
      Battery life (standby mode)4.0 day7.0 day

      Pros & Cons

      Pros
          Cons

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