#151B2C

Closest named color: Rich Black (#0D1B2A). oklch(22.5% 0.034 268.7), rgb(21, 27, 44).

Aa

White text reads best on this color (17.14:1).

About this color

#151B2C is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.034 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.013 away. White text reads best on it, at 17.14:1.

Hue familyBlues
Lightnessvery dark (23%)
Chromamuted (0.034)
Temperaturecool
Nearest nameRich Black (#0D1B2A)
Black text1.22:1
White text17.14:1

Values

HEX#151B2C
RGBrgb(21, 27, 44)
HSLhsl(224, 35%, 13%)
OKLCHoklch(22.5% 0.034 268.7)

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 #151B2C 17.14:1 AAA Lc -106.3 Preferred for body text
Black text on #151B2C 1.22:1 Fails Lc 0.0 Not readable
#151B2C text on white 17.14:1 AAA Lc 104.0 Preferred for body text
#151B2C text on black 1.22:1 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

    #F4F5F9

    oklch(97.1% 0.005 275)

  2. Step 100

    100

    #E6EAF2

    oklch(93.6% 0.012 264.5)

  3. Step 200

    200

    #D3D9E9

    oklch(88.6% 0.023 269.4)

  4. Step 300

    300

    #B5C0DC

    oklch(80.8% 0.041 268.5)

  5. Step 400

    400

    #8FA0CA

    oklch(70.8% 0.065 267.6)

  6. Step 500

    500

    #7488BD

    oklch(63.2% 0.084 268.1)

  7. Step 600

    600

    #5D71A9

    oklch(55.7% 0.091 268.4)

  8. Step 700

    700

    #4D5E91

    oklch(49.1% 0.085 269.1)

  9. Step 800

    800

    #3F4D76

    oklch(42.7% 0.071 268.9)

  10. Step 900

    900

    #35405F

    oklch(37.6% 0.055 268.7)

  11. Step 950

    950 (this color)

    #151B2C

    oklch(22.5% 0.034 268.7)

Export this scale for Tailwind in the Tailwind colors tool

#151B2C 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)#151D2D0.007
Deuteranopia (no green cones)#131B2C0.003
Tritanopia (no blue cones)#0D1E210.030
Achromatopsia (no color)#1B1B1B0.035

Harmonies

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

Complementary

The opposite hue (180°).

  • #151B2C

    #151B2C

    oklch(22.5% 0.034 268.7)

  • #221B07

    #221B07

    oklch(22.5% 0.035 90.3)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #151B2C

    #151B2C

    oklch(22.5% 0.034 268.7)

  • #0B1E2A

    #0B1E2A

    oklch(22.5% 0.034 238.5)

  • #1E182A

    #1E182A

    oklch(22.5% 0.035 298.9)

Open the analogous palette in the generator

Split complementary

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

  • #151B2C

    #151B2C

    oklch(22.5% 0.034 268.7)

  • #28180B

    #28180B

    oklch(22.7% 0.034 58.9)

  • #1A1E0B

    #1A1E0B

    oklch(22.5% 0.034 119)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #151B2C

    #151B2C

    oklch(22.5% 0.034 268.7)

  • #2A1512

    #2A1512

    oklch(22.4% 0.035 28.9)

  • #102013

    #102013

    oklch(22.5% 0.033 149.1)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #151B2C

    #151B2C

    oklch(22.5% 0.034 268.7)

  • #29151B

    #29151B

    oklch(22.6% 0.034 0.8)

  • #221B07

    #221B07

    oklch(22.5% 0.035 90.3)

  • #06211C

    #06211C

    oklch(22.5% 0.034 178.8)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #151B2C, closest first.

Similar named colors

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

Use #151B2C 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.