Sensibly Altocumulus
Sensibly Altocumulus (#BBB6C7) is a soft indigo with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (258°, 13%, 75%) places it in the muted band at a light lightness. It works as a background wash, large-area fill, or soft illustration tone. Add a darker ink of the same hue when you need type over it. For a confident two-color system, pair it with its complementary lime. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin sēnsibilis, perceivable / having-good-sense — adverbial-and-adjectival suffix -ly. As a color modifier, sensibly implies a neutral-and-practical-and-rational quality where the hue carries the visual register of practical-and-functional color-decision matched to its everyday-use context. Sits at the neutral-and-traditional end of the grid, parallel to reasonably and practical in usage.
Latin altus (high) and cumulus (heap) — the iconic pale-cool-pale-gray middle-altitude altocumulus mid-cloud-form, particularly the altocumulus mackerel-sky preceding warm-front weather. Altocumulus color refers to an altocumulus mackerel-sky over a Cornish-coast in late-October: a pale cool gray with the optical complexity of middle-altitude water-droplet scattering against partly-cleared autumn sky.
Closest matches
The nearest named color in three reference sources, ranked by perceptual distance (ΔE76 in CIELAB). ΔE < 1 is imperceptible to most viewers; ΔE > 10 is clearly different. When two sources point to the same hex they’re merged into one tile; click any to open that color’s page.
Variations
Click any swatch to exploreHarmonies
Accessibility
How this color appears to viewers with the four major color-vision-deficiency types. Computed via the Machado (2009) physiologically-based model. If a tile matches the original, the color reads the same to that viewer.
The color used as foreground text against pure white and pure black, with the contrast ratio and WCAG 2.1 grade. Aim for AA (4.5:1) for body text and AA Large (3:1) for 18 pt+ headlines; AAA (7:1) is the gold standard for long-form reading surfaces.
Wide gamut
The CSS Color 4 wide-gamut form of this color. Both swatches render the same color on every display — the P3 form only diverges from sRGB when a designer pushes channels outside sRGB's reach.
This color sits well within the sRGB cube. P3 and sRGB share the gray axis and most desaturated tones, so a P3 display renders this identically to an sRGB display.