#121B3A

Closest named color: Rich Black (#0D1B2A). oklch(23.3% 0.061 269.1), rgb(18, 27, 58).

Aa

White text reads best on this color (16.88:1).

About this color

#121B3A is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.061 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.033 away. White text reads best on it, at 16.88:1.

Hue familyBlues
Lightnessvery dark (23%)
Chromamuted (0.061)
Temperaturecool
Nearest nameRich Black (#0D1B2A)
Black text1.24:1
White text16.88:1

Values

HEX#121B3A
RGBrgb(18, 27, 58)
HSLhsl(227, 53%, 15%)
OKLCHoklch(23.3% 0.061 269.1)

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 #121B3A 16.88:1 AAA Lc -106.1 Preferred for body text
Black text on #121B3A 1.24:1 Fails Lc 0.0 Not readable
#121B3A text on white 16.88:1 AAA Lc 103.7 Preferred for body text
#121B3A 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

    #F3F5FC

    oklch(97.1% 0.01 273.4)

  2. Step 100

    100

    #E4EAF8

    oklch(93.7% 0.02 267.3)

  3. Step 200

    200

    #CED9F5

    oklch(88.6% 0.04 268.5)

  4. Step 300

    300

    #ADBFF0

    oklch(80.8% 0.072 269)

  5. Step 400

    400

    #839DE9

    oklch(70.7% 0.116 268.9)

  6. Step 500

    500

    #6583E2

    oklch(63.2% 0.147 268.7)

  7. Step 600

    600

    #4E6AD0

    oklch(55.6% 0.16 269.1)

  8. Step 700

    700

    #3F58B4

    oklch(49.2% 0.149 268.9)

  9. Step 800

    800

    #344892

    oklch(42.7% 0.124 269.2)

  10. Step 900

    900

    #2D3D74

    oklch(37.6% 0.096 269.2)

  11. Step 950

    950 (this color)

    #121B3A

    oklch(23.3% 0.061 269.1)

Export this scale for Tailwind in the Tailwind colors tool

#121B3A 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)#0C1F3B0.014
Deuteranopia (no green cones)#071B390.014
Tritanopia (no blue cones)#0022270.054
Achromatopsia (no color)#1D1D1D0.061

Harmonies

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

Complementary

The opposite hue (180°).

  • #121B3A

    #121B3A

    oklch(23.3% 0.061 269.1)

  • #271C00

    #271C00

    oklch(23.3% 0.048 88.1)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #121B3A

    #121B3A

    oklch(23.3% 0.061 269.1)

  • #002033

    #002033

    oklch(23.2% 0.052 239.1)

  • #221636

    #221636

    oklch(23.4% 0.061 298.9)

Open the analogous palette in the generator

Split complementary

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

  • #121B3A

    #121B3A

    oklch(23.3% 0.061 269.1)

  • #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.

  • #121B3A

    #121B3A

    oklch(23.3% 0.061 269.1)

  • #35100C

    #35100C

    oklch(23.3% 0.061 28.7)

  • #03250C

    #03250C

    oklch(23.3% 0.061 148.8)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #121B3A

    #121B3A

    oklch(23.3% 0.061 269.1)

  • #330F1D

    #330F1D

    oklch(23.3% 0.061 358.7)

  • #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 #121B3A, closest first.

Similar named colors

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

Use #121B3A 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.