In general, subtractive color dyes used for current inkjet printers (IJs) are selected from among many potential dyes. However, such trial-and-error approaches are inefficient, and there remain questions as to how to guarantee a truly optimum dye set. Thus, development of a computer simulation system to choose the optimum subtractive color dyes is an important goal.In a previous study, the Cellular Neugebauer model (CNM) was shown to achieve sufficient prediction accuracy. However, prediction by CNM requires knowledge of the spectral reflectances of the secondary colors included in the Neugebauer primary set, and hence it is very difficult to use for evaluating the hypothetical subtractive color dyes.Alternative models are available that rely only on the spectral reflectances of the primary colors. These include the Kubelka-Munk equation (KM) and the Williams and Clapper equation (WC). The drawback of these models is that they are most appropriately applied to prediction of color in photographic color paper. Fortunately, coated paper for dye-based color IJs has advanced to the point that there are now products available that are similar to that of a photographic color paper. The present study evaluates the prediction capability of KM and WC for high quality coated paper of dye-based color IJs.Furthermore, a novel approach has been proposed by taking into account dot gain. The color gamuts of dye-based color IJs have been calculated by means of a computer simulation. These have been compared with the color gamuts obtained by CNM.This study is an important step toward the development of simulations for use in improving image quality for dyebased IJ.