PurePulse® Technology

Continuous, automatic heart rate tracking right on your wrist—all from Fitbit.

Your heart is at the center of everything you do. It keeps you moving and keeps you motivated. That’s why tracking it is so important—for your health, for your fitness and for every part of your personal journey. Everything starts with heart.

Get the benefits of continuous heart rate:

Work toward your weight goals.

better calorie burn tracking

Losing, gaining or maintaining weight is about math: calories in vs. out. By measuring how hard your heart is working—both all day and during workouts—you get a better measure of total calories burned.

So, even if your favorite heart-pumping activities don’t affect your step count, you’ll still get the right credit for your effort.

Optimize your time spent on exercise

simplified zones

Tracking heart rate during workouts can help you maintain the right intensity, find a sweet spot for pace or avoid overtraining.

During workouts, use Fitbit’s heart rate zones to gauge how much effort you’re exerting and see if you should dial it up or dial it back. Afterward, check your workout summary in the Fitbit app to view your time in each zone and to follow improvements over time.

Understand the right zone for your goals

  • Fat Burn

    This moderate intensity zone boosts basic endurance and teaches the body to use fat as fuel.

    Common during:

    walking, pilates & yoga

  • Cardio

    This medium-intensity zone is great for increasing cardio fitness and muscle strength.

    Common during:

    running, dance & elliptical

  • Peak

    This maximum intensity zone is meant for short, intense training bursts aimed at improving performance.

    Common during:

    interval & endurance training

resting heart rate

Find easy ways to track health & fitness.

resting heart rate

Day-to-day, it can be tough to tell if the hard work on your health is paying off. Resting heart rate can be a great indicator of the changes to cardiovascular health, so you can see if you’re improving over time.

Find easy ways to track health & fitness.

resting heart rate

Know what's normal

For most people, resting heart rate is 60-100 beats per minute.1

Follow your progress

A decrease in resting heart rate typically indicates your cardio health is improving.2

Get a better reading

Wear your tracker while you sleep for a more accurate number.

Why resting heart rate matters

cardio fitness

Find easy ways to track health & fitness.

cardio fitness

Get a better understanding of your fitness level and see how it compares to people of the same age and gender with a personalized Cardio Fitness Score from Fitbit Charge 2.

cardio fitness

cardio fitness

Know where you stand

Get a snapshot of your cardio fitness and note changes over time.

Get ideas to improve

See how increasing exercise or achieving a healthy weight can improve your fitness level.

learn more

Make managing stress a lot less stressful.

guided breathing sessions

Research shows that guided breathing can help reduce stress3 and anxiety4—and can even lower blood pressure.5 With personalized guided breathing sessions based on your heart rate, Charge 2 makes it easy to find moments of calm throughout the day.

Watch the video Play the demo

Behind the scenes of PurePulse technology.

When the heart beats, capillaries expand and contract

Green LED lights reflect off the skin to detect that change in blood flow

PurePulse then uses that data to track your beats per minute

Why Fitbit is Different:

Uses ultra low-power battery technologies, so you get longer battery life—even with continuous heart rate readings.

Tracks heart rate automatically and continuously, without any button-pushing and without an uncomfortable chest strap.

Here’s how to wear your heart rate tracker.

  • All Day

    Wear your band lower on your wrist, and loosely enough that it can move back and forth.

  • During Workouts

    Wear the band 2-3 finger widths above your wrist bone—and keep it secure, but not too tight.

See More Tips

Choose a tracker with heart:

Learn more about heart rate on the Fitbit blog: