Provided is a profile creation method for creating a color conversion profile for an image forming apparatus which forms an image by performing, on an input color value having total use amount of color material exceeding set amount, a process for reducing the total use amount, by interpolating lattice points in a look-up table. The profile creation method includes: determining whether a point of an input color value with the total use amount of color material being equal to the set amount exists between two adjacent lattice points in the look-up table; and, when it is determined so, calculating an output color value of an interpolation point set between the two lattice points, by a polynomial interpolation method for performing interpolation calculation by using, besides output color values of the two lattice points, an output color value of a lattice point other than the two lattice points.