Interpolation calculates intermediate values in animations that change HTML properties such as height, width, etc. Color interpolation defines intermediate values of colors in color mixing, gradients, compositing, filters, transitions, animations, and color functions.

Interpolations aren't necessarily linear. Most interpolated values are real, floating-point numbers; however, when there is no mid-point between two values, such as values that accept only integers, the interpolation is discrete . The progression of interpolation also depends on easing functions in animations and color stops, and color and hue interpolation methods in gradients.

In JavaScript, the term "interpolation " is used as a description of the substitution of strings in the template literals.