#121B3D

Closest named color: Rich Black (#0D1B2A). oklch(23.5% 0.066 269.6), rgb(18, 27, 61).

Aa

White text reads best on this color (16.80:1).

About this color

#121B3D is a very dark, muted blue. In OKLCH its lightness is 24%, its chroma 0.066 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.039 away. White text reads best on it, at 16.80:1.

Hue familyBlues
Lightnessvery dark (24%)
Chromamuted (0.066)
Temperaturecool
Nearest nameRich Black (#0D1B2A)
Black text1.24:1
White text16.80:1

Values

HEX#121B3D
RGBrgb(18, 27, 61)
HSLhsl(227, 54%, 15%)
OKLCHoklch(23.5% 0.066 269.6)

Contrast

WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.

PairWCAG 2ResultAPCAAPCA guidance
White text on #121B3D 16.80:1 AAA Lc -106.0 Preferred for body text
Black text on #121B3D 1.24:1 Fails Lc 0.0 Not readable
#121B3D text on white 16.80:1 AAA Lc 103.6 Preferred for body text
#121B3D text on black 1.24:1 Fails Lc 0.0 Not readable

Tints and shades

A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 950.

  1. Step 50

    50

    #F2F5FD

    oklch(97% 0.011 269.6)

  2. Step 100

    100

    #E4EAFA

    oklch(93.7% 0.023 269.4)

  3. Step 200

    200

    #CDD9F7

    oklch(88.6% 0.043 268.2)

  4. Step 300

    300

    #ACBFF4

    oklch(80.9% 0.078 269.3)

  5. Step 400

    400

    #829CEF

    oklch(70.7% 0.125 269.8)

  6. Step 500

    500

    #6481E9

    oklch(63.1% 0.159 269.7)

  7. Step 600

    600

    #4C68D8

    oklch(55.7% 0.174 269.4)

  8. Step 700

    700

    #3E55BB

    oklch(49% 0.162 269.9)

  9. Step 800

    800

    #334797

    oklch(42.8% 0.133 269.5)

  10. Step 900

    900

    #2C3C78

    oklch(37.6% 0.104 269.6)

  11. Step 950

    950 (this color)

    #121B3D

    oklch(23.5% 0.066 269.6)

Export this scale for Tailwind in the Tailwind colors tool

#121B3D with color blindness

Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.

VisionSeen asShift (ΔE)
Protanopia (no red cones)#0A1F3E0.015
Deuteranopia (no green cones)#031B3C0.019
Tritanopia (no blue cones)#0023290.057
Achromatopsia (no color)#1D1D1D0.066

Harmonies

Hue rotations in OKLCH that keep this color's lightness and chroma.

Complementary

The opposite hue (180°).

  • #121B3D

    #121B3D

    oklch(23.5% 0.066 269.6)

  • #271D00

    #271D00

    oklch(23.6% 0.048 90.5)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #121B3D

    #121B3D

    oklch(23.5% 0.066 269.6)

  • #002135

    #002135

    oklch(23.6% 0.054 239.9)

  • #231538

    #231538

    oklch(23.4% 0.066 299.8)

Open the analogous palette in the generator

Split complementary

The two hues beside the complement (150° and 210°).

  • #121B3D

    #121B3D

    oklch(23.5% 0.066 269.6)

  • #311600

    #311600

    oklch(23.5% 0.056 58.2)

  • #1B2200

    #1B2200

    oklch(23.7% 0.056 120.3)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #121B3D

    #121B3D

    oklch(23.5% 0.066 269.6)

  • #370F0A

    #370F0A

    oklch(23.5% 0.065 29.9)

  • #00260B

    #00260B

    oklch(23.5% 0.066 149.3)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #121B3D

    #121B3D

    oklch(23.5% 0.066 269.6)

  • #360E1D

    #360E1D

    oklch(23.7% 0.066 0.3)

  • #271D00

    #271D00

    oklch(23.6% 0.048 90.5)

  • #00251F

    #00251F

    oklch(23.7% 0.043 179.4)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #121B3D, closest first.

Similar named colors

The eight closest entries in our named color list, with their ΔE distance.

Use #121B3D in your product

Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.