Is Charge 4 more or less accurate than Versa 3?

[funkytwig]

I have both and trying to decide which to keep.  None of the reviews I have indicates either way.  I have both on and the heart rate differs by 4 after doing 8 readings of each at the same time and doing average but wondered if anyone had done any full testing of all the sensors.

Moderator Edit: Clarified subject

[SilviaFitbit]

@funkytwig Hi there. Thank you for the details mentioned. 

Glad to hear that you'll continue being a Fitbit user. At times, you might notice slight variations between your heart-rate reading on your Fitbit device versus on another device (such as a chest strap or another wrist-based heart-rate tracker) due to the differences in technologies.

Differences between heart-rate readings on your device and on exercise equipment are likely due to wrist or hand position. Make sure the back of your device is in contact with your wrist and that your band is snug.

Note that you might notice slight variations between your heart-rate reading on your new Fitbit devices compared with your old ones due to improvements in the heart rate sensor and algorithm.

Learn more about it in this article. 

Hope this helps. 

[ac_devel]

Hi! Is there a way to find out which algorithms run on devices? For instance the sleep stages algorithm, is the same between Charge 4 and Versa 3?
Also can we compare the hardwares used for PPG between devices?