What is disclosed is a novel system and method for generating a color lookup table (LUT) that minimizes interpolation errors over the entire color space, including the off-grid colors. The present method for LUT optimization considers off-grid point errors in assigning entries to the LUT. As described herein further, grid point values are computed that provide a least mean square error solution for the entire printer gamut volume. The present method dramatically reduces errors near the gamut boundary and can be used for populating nodes of any LUT that will be linearly interpolated, not only a table mapping from L*a*b* to CMYK.