#121B3C

Closest named color: Rich Black (#0D1B2A). oklch(23.4% 0.064 269.4), rgb(18, 27, 60).

Aa

White text reads best on this color (16.83:1).

About this color

#121B3C is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.064 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.037 away. White text reads best on it, at 16.83:1.

Hue familyBlues
Lightnessvery dark (23%)
Chromamuted (0.064)
Temperaturecool
Nearest nameRich Black (#0D1B2A)
Black text1.24:1
White text16.83:1

Values

HEX#121B3C
RGBrgb(18, 27, 60)
HSLhsl(227, 54%, 15%)
OKLCHoklch(23.4% 0.064 269.4)

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 #121B3C 16.83:1 AAA Lc -106.0 Preferred for body text
Black text on #121B3C 1.24:1 Fails Lc 0.0 Not readable
#121B3C text on white 16.83:1 AAA Lc 103.6 Preferred for body text
#121B3C 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

    #F3F5FD

    oklch(97.1% 0.011 274.9)

  2. Step 100

    100

    #E4EAF9

    oklch(93.7% 0.021 268.4)

  3. Step 200

    200

    #CED9F6

    oklch(88.6% 0.042 269)

  4. Step 300

    300

    #ADBFF3

    oklch(80.9% 0.076 269.8)

  5. Step 400

    400

    #829CED

    oklch(70.6% 0.123 269.6)

  6. Step 500

    500

    #6481E7

    oklch(63% 0.157 269.6)

  7. Step 600

    600

    #4D68D5

    oklch(55.5% 0.17 269.7)

  8. Step 700

    700

    #3E56B9

    oklch(49.1% 0.158 269.5)

  9. Step 800

    800

    #334795

    oklch(42.6% 0.13 269.4)

  10. Step 900

    900

    #2C3C77

    oklch(37.6% 0.102 269.5)

  11. Step 950

    950 (this color)

    #121B3C

    oklch(23.4% 0.064 269.4)

Export this scale for Tailwind in the Tailwind colors tool

#121B3C 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)#0B1F3D0.014
Deuteranopia (no green cones)#041B3B0.017
Tritanopia (no blue cones)#0022280.055
Achromatopsia (no color)#1D1D1D0.065

Harmonies

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

Complementary

The opposite hue (180°).

  • #121B3C

    #121B3C

    oklch(23.4% 0.064 269.4)

  • #271C00

    #271C00

    oklch(23.3% 0.048 88.1)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #121B3C

    #121B3C

    oklch(23.4% 0.064 269.4)

  • #002134

    #002134

    oklch(23.5% 0.053 238.5)

  • #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°).

  • #121B3C

    #121B3C

    oklch(23.4% 0.064 269.4)

  • #301600

    #301600

    oklch(23.3% 0.055 59.3)

  • #1B2100

    #1B2100

    oklch(23.3% 0.055 119.1)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #121B3C

    #121B3C

    oklch(23.4% 0.064 269.4)

  • #370F0B

    #370F0B

    oklch(23.5% 0.065 28.7)

  • #01260C

    #01260C

    oklch(23.5% 0.064 149.5)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #121B3C

    #121B3C

    oklch(23.4% 0.064 269.4)

  • #350E1D

    #350E1D

    oklch(23.5% 0.065 359.5)

  • #271C00

    #271C00

    oklch(23.3% 0.048 88.1)

  • #00241E

    #00241E

    oklch(23.3% 0.043 179.1)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #121B3C, closest first.

Similar named colors

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

Use #121B3C 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.