色度学（Colorimetry），又名比色法，是量化和物理上描述人们颜色知觉的科学和技术。 色度学同光谱学（spectrophotometry）相近，但是色度学更关心的是于人们颜色知觉物理相关的光谱。最常用的是CIE1931色彩空间和相关的数值。

Colorimetry (American English) or Colourimetry (British English; see spelling differences) is "the science and technology used to quantify and describe physically the human color pe****tion." It is similar to spectrophotometry, but is distinguished by its interest in reducing spectra to the physical correlates of color pe****tion, most often the CIE 1931 XYZ color space tristimulus values and related quantities.