my pulse ox number is always wrong

My Vivo 4 was always low, the Venu 2 is much better but still a little low. But it's like 94 or 95 when the devices at my doctor read 98 or 99. I do still frequently get Check Fit messages. Have you tried it overnight? It uses a bit of battery but it might be a good test. All that said, your situation sounds like a sensor problem to me. I bet if you called for service Garmin would replace the watch.

Thanks for the thought, but I am already on my second version of this watch.  #2 has the same problems, all of them, as #1.

Must be a Florida thing. KIDDING . Before my Garmin I had a Samsung Active 2. People on their forums were complaining that tattoos or birthmarks or other skin abrasions caused erroneous readings. Maybe another experiment would be to turn on pulse ox for sleep and wear the watch on the other arm overnight and see what you get.

Yes, as suggested, try the other wrist. How loose or tight do you wear the watch? I find mine doesn't like being too loose or tight, just resting lightly on my wrist seems best. Mine is usually within 2% of a finger tip instrument when fitted this way.

I am also having the same issues. This is definitely 3 to 5% lower than pulse ox on my finger. Does not seem like a helpful feature which stinks because this was a major reason why I purchased this watch. 

Maybe you should've bought a medical grade watch, since Garmin's devices aren't certified and probably won't be in the forseeable future. Pulse Ox on Garmin watches is only useful for training at higher altitudes imo.  

Accuracy of Wrist-based Pulse Ox

Pulse Oximetry (Pulse Ox) readings are available for certain Garmin wearables. It can provide an estimation of the user’s peripheral blood oxygen saturation (SpO2%) at any given time the feature is accessed. The feature can also be set to track in a continuous manner during a period while the user is asleep. For certain devices, it can also be used to track periodically throughout the day along with a view of the user’s altitude or elevation.

While every effort is made to ensure a high degree of accuracy, there are certain limitations that can cause inaccurate measurements. The user’s physical characteristics, fit of the device, and presence of ambient light may impact the readings. Garmin may release device software over time to improve aspects of the measurements. The Pulse Ox data is not intended to be used for medical purposes, nor is it intended to diagnose, treat, cure or prevent any disease or condition.

Excessive motion and the position of the device can impact the accuracy of the readings. It is important to keep your arm/sensor still for approximately one minute for best accuracy.

Yeah I hear that but why even make it an option to monitor during sleep if it isn't accurate? Maybe I'll call and see if it could be a sensor malfunction. 

I don’t think it probably is.  I find they’re just pretty must low all the time though if I press it on my wrist while taking the reading I usually will get a much more accurate reading of 98-99%.  The watch has so many useful and great qualities but blood OX is really more of a “general” vs medical reading.

@CindiL OMG! You made my pulseox to work better! Thank you for it!

Thanks to this what you wrote

CindiL said:

if I press it on my wrist while taking the reading I usually will get a much more accurate reading of 98-99%.

I fastened the strap just by one hole tighter, and WOW, just have no 80% yellow erroneous  indications but 94-98 green good ones, significantly better than those with the strap fastened looser.

I was afraid to fasten the watch strap tighter, because I read in Garmin manual that it should be fastened not too tight, but now the pulseox is much more better