Why doesn't my GPS/pedometer match the map?

  1. megarun37 says:

    So I have an iPod with the pedometer thing in it, and it is always underestimating my mileage, compared to the gmap-pedometer. Which one is most accurate, and which should I go by?

  2. drkarlpt says:

    For me, comparing gmaps-pedometer with my GPS smartphone app, MapMyWalk, it is gmaps-pedometer that understimates mileage. I've noticed this for awhile, but today did a really long walk and it was a huge difference. Gmaps pedometer says it was 3.28 miles; MapMyWalk with GPS says it was 4.79 miles. That is a totally unacceptable difference. I know that GPS can be thrown off with satellite date, but not by that much,a nd I was going at a pretty fast clip, so I anticipated it being a little over45 minutes but it was about 80 minutes. So ther eis NO WAY the gmaps-pedometer is accurate. I just posted this map to public here: http://www.gmap-pedometer.com/?r=6211135

  3. drkarlpt says:

    As for the iPod pedometer, I do think that pedometers in general are not that accurate, unless each and every step you take is similar in motion. And it probably underestimates your *distance* if you have longer legs than the average woman (and if you're a guy, that really explains it!). I'm 6'2" (part of why I can easily walk at 4mph), so my strides are a lot longer than the average woman's!