# [Proj] Length of a deg in metres

Charles Karney charles.karney at sri.com
Thu Nov 8 13:06:37 EST 2018

```Dunno about getting the result from proj.  The formula you want is given
in

https://en.wikipedia.org/wiki/Longitude#Length_of_a_degree_of_longitude

This includes the ellipsoidal correction.

On 11/8/18 10:18 AM, Nicolas Cadieux wrote:
> Hi,
>
> I am writing to python code to calculate the length (in metres) of a
> degree of longitude at a certain degree of latitude.  I would like to
> take various ellipsoid in mind (WGS84, GRS80, Clarke 1866...).  The goal
> is to find the right scale (or z factor) when making slope or shade
> raster models when x and y are in long/lat and z in feet or meters.  Can
> someone point me in the right direction to do this in using Proj?  Is
> Proj the best option for this?
>
> Thanks,
>
> Nicolas
>
> _______________________________________________
> Proj mailing list
> Proj at lists.maptools.org
> http://lists.maptools.org/mailman/listinfo/proj
>
```

More information about the Proj mailing list