How Does FitBit Works In Tracking Steps and Calories Burnt.

If you’re anything like me, you would want to know the science behind the fitness tracker that you intend to buy or already using on daily basis.

I have several post about fitbit tracker on my website, so I think it would be nice to have a detailed post that discuss the working mechanism of fitbit trackers.

I would discuss the functioning mechanism of fitbit trackers by listing how the basic features you would find in a typical fitbit tracker and then explain how the
tracker works in getting accurate data.

how does fitbit works


Fitbit device has an in-built accelerometer (3-axis). What the accelerometer does is to understand your movement. It typically convers your motion into a measurable

When you have a fitbit attached to your wrist or any other part of your body, the in-built accelerometer would take note of your motion and then convert it into data.

Take the fitbit zip activity tracker for example, it has a 3-axis in-built accelerometer. Older version of pedometers have just a single axis accelerometer, which makes the step count less accurate as compared to the modern fitbit trackers.

You might be wondering, how does the device differentiate between walking, running and climnbing stairs.

The same principle applies to the three forms of motion. But fitbit trackers are built with advanced algorithm that studies the movement pattern to categorize it as
step, climb or running.

Take for instance, your pace while walking would not be as fast as when you’re running. While that of when you’re climbing a stairs or some sort of cliff.

The device has been designed in such a way that it does not record any data while driving or flying in an airplane.


Another feature that comes with a typical fitbit device is the calories measurement. A typical fitbit tracker can measure the amount of calories burnt during physical

For this feature to work accurately, fitbit would require you to input your age, height, weight as well as gender.

These data is then used in calculating your BMR (Basal Metabolic Rate), which is the name given to the rate at which your body use up calories while you;re at rest.

Fitbit will then use their software to calculate the amount of calories you burn during a period of time by taking into account the data provided from the device against the initially supplied data while setting up your account.


Fitbit tracker are capable of tracking sleeping pattern.¬†However, the accuracy of the data provided depends on the type of fitbit device you’re using.

Fitbit One, zip and flex does not have much accuracy because you’re expected to set the time of sleep (or inactivity) yourself, so it basically relies on your little movement to determine how much of sleep you’re getting.

If you’re the type that move around in bed a lot, then fitbit would record that you have poor sleeping pattern. The science behind sleep tracking for fitbit device is not close to perfect. But in some high end fitbit device like the alta, charge and others, the sleep tracking mode is automatically activated based on minimal movement.


In conclusion, various research are being conducted on daily basis to improve the functionality of these device, and we can only hope that the accuracy would be top notch in the nearest future.

About Author:

Living a healthy live does not have to be a tug of war... We can be healthy without starving ourselves to death. Let's explore the technology side of healthy living together. Join me in my journey as I check the good, the bad and the ugliest of technology for kids and family altogether.

Leave A Comment

Your email address will not be published. Required fields are marked *