Strava vs Google maps vs iPod nano distance tracking

Help, does anyone know an accurate way to map distance

So far I have used for a route that was on sidewalks and on trails that were in Google map
Strava got distance of 3 miles when walking
Google maps: gave me an estimated distance of 2.8 miles
iPod Nano: used when running this morning said the same route was only 2.5 miles.

It makes a big difference to me because I ran it twice this morning so I ran somewhere between 5-6 miles. I'm trying to keep track of my pace to improve so even 5.6 to 6 miles makes a big difference.

Money is a little tight so I don't want to spend more than 20$ if there is a better tool out there to map distances.

Otherwise I'll take app recommendations unless Strava is the gold standard then I'll just keep using it.

Replies

  • shadow2soul
    shadow2soul Posts: 7,692 Member
    edited September 2018
    If I had to take a guess, the iPod Nano is using a default stride length to determine distance. This can throw off distance if your stride length is different than the default.

    Strava and google maps are using GPS.
  • CarvedTones
    CarvedTones Posts: 2,340 Member
    edited September 2018
    They probably all use GPS (correction - seeing above post that came in while typing; apparently nano does not) and almost certainly use the same formulas for distance. The difference is often how many points they plot. With few exceptions, GPS modules report position twice a second which turns into an awful lot of data points if you run a couple of hours, which some people do regularly. So they may record every couple of seconds. The trouble with that is the track ends up cutting corners and makes small curves into straight lines. This shortens distance very slightly. But, GPS isn't really as deadly accurate as it appears on mapping software. The actual raw data has occasional bounces off the track that have to be discarded. Software that isn't good at that can make the distance longer. If you can zoom in really close in their web interface, you can see the little variations in your route and see which one appears the most accurate to you. I am happy with Strava for paddling SUP; I think it's highly accurate.

    I am a nerd who has done some low level robotics programming using a GPS data stream. :smiley: