cividis

Cividis is a perceptually uniform colormap designed to be legible for viewers with color vision deficiency. It is intended as an accessible alternative to color maps that rely heavily on red–green contrasts, and it preserves the ordering of data for people with and without color vision deficiency.

The palette progresses from dark blue through blue-green to yellow, providing a smooth, continuous gradient. Its design emphasizes a monotonic luminance ramp so that differences in data are reflected primarily by perceived brightness, and the gradient remains readable when converted to grayscale. This makes cividis usable in a variety of display conditions and for printed materials.

Cividis was developed for scientific visualization and is implemented in major plotting libraries, notably Python’s Matplotlib, where it appears as a built-in option. It can be used in the same way as other colormaps by assigning it to the color map parameter in plotting routines. The palette is commonly described as color-vision deficiency–friendly, aiming to be distinguishable across common deficiency types such as deuteranopia and protanopia, while still providing appeal to viewers with normal vision.

Relation to other palettes: Cividis is part of the broader spectrum of perceptually uniform color maps and is often mentioned alongside viridis, plasma, and similar schemes as a choice when accessibility is a priority. While it shares the goal of perceptual uniformity with these palettes, it specifically prioritizes color-vision accessibility in its design choices.