Auxiliary latitudes map a spheroid onto a sphere, allowing an spheroidal problem to be converted into a simpler spherical one. Auxiliary latitudes are used extensively in geodesy and map projection (Karney 2023).
The six auxiliary latitudes are summarized in the following table (Karney 2023).
 | description |
 | (common) latitude |
 | parametric latitude |
 | geocentric latitude |
 | rectifying latitude |
 | conformal latitude |
 | authalic latitude |
In addition, there are three generic auxiliary latitudes denoted 
, 
, and 
, together with the colatitude 
. The isometric
latitude 
is not included in this list since it does not behave as an angle (in particular,
it diverges at the poles; Karney 2023).
