#1805DBUltramarine (#1805DB) is a dark, vivid blue with an OKLCH hue of 267°, lightness 0.41 and chroma 0.274. It sits on the cool side of the color wheel. In practice it behaves as an accent color: strong in focal moments, dominant over large fields.
| HEX | #1805DB |
|---|---|
| RGB | rgb(24, 5, 219) |
| HSL | hsl(245, 96%, 44%) |
| HSV | hsv(245, 98%, 86%) |
| CMYK | cmyk(89%, 98%, 0%, 14%) |
| CIE Lab | lab(27.9 69.8 -94.7) |
| OKLCH | oklch(0.410 0.274 267) |
Under warm 2700K interior light Ultramarine shifts noticeably: leans toward purple, loses intensity; in north-facing or shaded light it is virtually unchanged. Overall drift across common illuminants is small (max ΔE ≈ 2.5), so it is a lighting-stable choice.
#2413ce — ΔE 2.5, shifts noticeably: leans toward purple, loses intensity#1f0fd7 — ΔE 1.1, shifts only faintly, with no single dominant change#1805db — ΔE 0.0, is virtually unchanged#1701de — ΔE 0.5, is virtually unchangedAgainst white it measures 10.08:1 and against black 2.08:1, so white text is the stronger pairing. That pairing passes WCAG AA for body text. Avoid black text on this color entirely.
One color explored: close hues with real lightness and chroma structure, so the palette is the anchor through value rather than a set of colors.
#6e95ff · #3862fe · #1805db · #0e009d · #030050 · #010013
The anchor's neighbours on the wheel — everything shares an undertone, so the chord carries color without anything having to be muted to get along.
#0075a3 · #005ca4 · #1805db · #3800a0 · #39006c · #300041
The mid-gap pairing — sage and mustard, terracotta and olive. A foil rotated 40–65° toward warm or cool: too far to be kin, too near to argue, carried by temperature and a deliberate value offset.
#c980dd · #c425e8 · #874897 · #1805db · #0d0098 · #040059
One deliberately opposed voice — a single restrained counterpoint across the wheel, or temperature against temperature where the anchor is too muted to carry a loud opposite.
#f3bb00 · #6385dc · #536799 · #1805db · #0d1e78 · #030b3e
The anchor as the only color in the room. True neutrals or complement-warmed near-neutrals let it stay dominant.
#fdf1d5 · #98a7cb · #6b6250 · #1805db · #233154 · #0a0400
This color as a ground rather than a subject — its own restraint held across a narrow value band, carrying one saturated voice from the opposite temperature.
#f6f1e6 · #d0cbbe · #a6a091 · #332b19 · #110900 · #1805db
The opposite hue on the perceptual wheel, tempered to field strength — warm/cool tension without vibration.
#fff1d0 · #d0a000 · #7d5e00 · #1805db · #423000 · #010013
The complement's two neighbours instead of the complement itself — strong contrast with a lower clash risk.
#fff1d0 · #f88500 · #606b00 · #1805db · #502600 · #010100
Three hues spaced evenly around the wheel; the anchor leads and the other two are held at supporting strength.
#ffedeb · #ff786d · #007928 · #1805db · #003f10 · #080000
Two complementary pairs offset by 90° — the richest chord, kept usable by a strict lightness hierarchy.
#ffecf2 · #ff6daa · #7d5e00 · #1805db · #003d32 · #0a0400
#284BEB · #4771F9 · #6E95FF · #99B6FF · #C4D6FF
#1300BC · #0E009C · #09007E · #050061 · #030046
#1930BC · #243F9E · #324780
Its chroma is high enough to carry accents, calls to action, and focal moments; large fields of it will dominate a composition. In palettes it pairs most predictably with its tonal ramp and analogous neighbors; reserve the complementary hue for small, deliberate contrast.