Fitbit accuracy

sharon9597

Hi
Well I've had my Fitbit charge HR for 3 weeks and have been really pleased with it until today and now I'm not so sure. I went for a long walk and logged it using map my walk on my iPhone. So this obviously knows exactly where I've walked and how far. It said I had walked just over 8.5 miles at a speed of 3mph and did just over 21000 steps. When I checked my Fitbit record it recorded 8 miles, 2.5 mph and just over 20000 steps! This is quite a difference and of course it's the Fitbit data that shows on my fitness pal. Surely I am right in saying the map my walk is the most accurate as it uses a GPS signal mapping my exact walk which makes the Fitbit quite a bit out.
Does anyway else have similar experiences?

WestCoastJo82

I actually don't think that's much of a difference at all. Since .5 miles is about 1000 steps for the average person, it sounds like your FitBit is missing a few of your steps. There's instructions on the FitBit site for how to adjust sensitivity if lots of steps are being missed, but really losing 1000 steps out of 20,000 seems like a really small thing to worry about.

NancyN795

You might want to increase your stride length in your FitBit settings. The 1000 step difference isn't that big (<5%), but the distance is off by slightly more (5.9% - still not that bad, really). So, if you want to customize your stride length, here is the math:

(8.5 miles (from MMW) * 5280 ft/mile)/20000 FitBit steps = 2.244 ft/step (or 2ft 2.9 inches). Then, see if your distance is closer on your next walk.

While it might be more accurate to calibrate your stride length on a treadmill (as heybales has recommended elsewhere), some of us find it inconvenient to find a treadmill to do it on. So, I've calibrated mine on my regular walks and now my FitBit comes quite close to MMW as far as distance is concerned. MMW wants to give me more calories, but I think I trust my Charge HR for that. MMW doesn't have heart rate data.

Also, how do you get MMW to give you steps? Is that a feature that you have to subscribe to get? (To me, $6 a month seems awfully pricey.)

heybales

The GPS won't be that accurate either if you had many corners.

Did it say it was at the best 15 ft accuracy possible?

Even there, that can be 15 ft bouncing around.

But corners definitely lose accuracy.

Try looking at the path of the walk and confirm it's where you really were before trusting it too much.

sharon9597

Ok thanks, put like that I guess it's pretty good, 1000 steps just sounded a lot! Have to say other than that have been loving it, along with the whole Fitbit, map & mspmywalk sync. So easy and has really kept me on track making me want to keep up my new healthy eating and fitness regime.