Resting heart rate seems to be much higher than on Apple watch

[SunsetRunner]

I use both Apple watch and the Fitbit Charge 3. I have noticed that on the Fitbit Charge 3, the resting heart rate is much higher than what my Apple watch is registering. Is there a reason for this. By the way, my Charge 2 was the same as the Charge 3. Always registering a much higher resting heart rate. 

Any suggestions as to why this is the case??

[pilv13]

Apple watch 3, right?

Well.. how these devices usually work with the LEDs, first of all blood is red because it reflects red light and absorbs green light. Right? Therefore, by using green LEDs and pairing them with photodiodes, which receive reflected light, the trackers are able to detect the amount of blood flowing through the wrist. When your heart beats the amount of green light being absorbed is greater. Between beats it's less. To get accurate data the LED(s) needs to blink really fast. And then you have to run algorithms to compensate for any number or errors and fluctuations, which is probably where the discrepancies happen.

Sometimes environmental conditions or skin reflectivity or bad software algorithms or any number of other reasons can influence the outcome.

And if you have Apple watch 4, then what are you doing slumming here with us? That thing has medical grade ECG based HR monitor, it doesn't get any better than that.

[SunsetRunner]

pil13, much appreciate your comments. I was using the Apple watch 3. I have been looking at the Apple watch 4 but was not aware that the heart monitor was that much better than the Apple watch 3. I like the small size of the Charge 3, was hoping to escape the Apple eco system if possible.

[Jasrboyd]

So which one is most accurate the fit bit or iwatch3?

[ChristofS]

I hate to Necro this thread BUT...I have same problem. My Fit Bit versa Resting heart Rate (RHR) is higher than on my Apple Watch 3 the wife recently bought me.  My Fitbit RHR is usually 63 bpm where as. My Apple Watch says my RHR is 47 bpm...huge difference. I think it’s because the Apple Watch checks your BPM every 10 minutes where as the fit Bit versa,in my case, records BPM constantly.

[Buddrball]

I have the same issue when comparing Versa to Apple Watch 5. I was always confused how my Fitbit RHR was calculated because my HR when I slept was always much lower than what they reported. For example, my RHR might be reported as 75, but my sleep RHR looks like it’s 60. My best guess is that Fitbit is averaging a resting heart rate over the entire day, not just sleep, whereas Apple is looking at the minimum HRH when you sleep. It would be helpful if both would define how they’re reporting RHR. 

[ChristofS]

Right. My RHR on Apple Watch is 52. On Fitbit Versa, it’s a solid 60-63

Sent from my iPhone

[Vishalk]

I have not used apple but can tell Fitbit RHR is way higher. Many times it shows RHR higher than the max HR in morning.

When I port same data to Google FIT it shows my RHR lower by 10-14 BPM. Fitbit algorithm is mess for RhR.