Achromatic palette
A palette with the hue dial turned off: only black, white, and grays, with lightness doing all the separating.
See it
What it is
An achromatic palette contains no hue: only white, black, and the grays between them. In digital color terms, its channels are equal in sRGB or its chroma is zero in OKLCH. It is stricter than monochromatic, which can use many light and dark versions of blue, red, or any other single hue.
Reach for it when shape, type, texture, and value hierarchy should do all the talking. Editorial layouts, wireframes, luxury packaging, and photographic portfolios often use the constraint well. Ansel Adams' Zone System is a useful anchor: a black-and-white image can still hold a full ladder of deliberate tonal steps.
Gotcha: removing hue does not make the palette simple. With no color to separate roles, adjacent grays need enough lightness difference to keep cards, controls, and text legible. Avoid filling the middle with a dozen barely different grays, and measure every text pair instead of trusting the clean black-and-white moodboard.
Ask AI for it
Rebuild this interface as an achromatic palette using CSS oklch() colors with chroma fixed at 0. Create nine lightness steps from 98% to 12%, map them to background, surface, border, disabled, muted text, body text, and heading roles, and expose each role as a CSS custom property. Keep one full step between adjacent surfaces, verify normal text against its background with the WCAG 2 contrast formula at 4.5:1 or better, and do not introduce any nonzero chroma.