Enter a color, and the tool applies the classic sepia photo-tone matrix to it.
A warm brownish tint reminiscent of old photographs, produced by a fixed color matrix applied to each RGB channel.
The widely-used sepia matrix: R'=0.393R+0.769G+0.189B, G'=0.349R+0.686G+0.168B, B'=0.272R+0.534G+0.131B, clamped to 0–255.
This tool tones a single color. For images, apply the same matrix as a CSS or canvas filter across every pixel.