WalkJogRun.net & goodrunguide.co.uk giving me different distances!!

[Oldgirl]

Does anyone use these websites to measure their runs?

I have been using GoodRunGuide for ages now (£10 p/a) and was quite happy with it. Then someone at the gym suggested I try WalkJogRun.net (free) and more accurate. So this afternoon I have entered two of my runs into it. Both have logged different distances. One route is only 2.5Km which I have been using for faster runs, this has measured 2.65Km, but more of a shock my 5.01Km on GRG has measured 5.37Km on WJR website. I know if you are doing the same runs you will be able to compare your times which is fine but if its not measuring correctly you are not going to get an accurate time per Km overall. Just wondered if anyone else has found differences when using these sites?

[TJFlute]

I don't know about comparing the sites because I haven't used walkjogrun yet, but when I compare my garmin measuring results with goodrunguide they are pretty much identical.