#B21F31

Closest named color: Firebrick (#B22222). oklch(49.7% 0.18 21.3), rgb(178, 31, 49).

Aa

White text reads best on this color (6.70:1).

About this color

#B21F31 is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.180 and its hue 21°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.017 away. White text reads best on it, at 6.70:1.

Hue familyReds
Lightnessmedium-dark (50%)
Chromavivid (0.180)
Temperaturewarm
Nearest nameFirebrick (#B22222)
Black text3.13:1
White text6.70:1

Values

HEX#B21F31
RGBrgb(178, 31, 49)
HSLhsl(353, 70%, 41%)
OKLCHoklch(49.7% 0.18 21.3)

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 #B21F31 6.70:1 AA Lc -86.5 Fine for body text
Black text on #B21F31 3.13:1 AA large text Lc 22.7 Dividers and decoration only
#B21F31 text on white 6.70:1 AA Lc 81.4 Fine for body text
#B21F31 text on black 3.13:1 AA large text Lc -20.5 Dividers and decoration only

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 700.

  1. Step 50

    50

    #FDF3F2

    oklch(97.2% 0.011 24.3)

  2. Step 100

    100

    #FBE4E2

    oklch(93.7% 0.025 23.6)

  3. Step 200

    200

    #F8CDCB

    oklch(88.5% 0.049 21.2)

  4. Step 300

    300

    #F4AAA8

    oklch(80.8% 0.088 20.9)

  5. Step 400

    400

    #EB7A7A

    oklch(70.8% 0.14 21.2)

  6. Step 500

    500

    #E15158

    oklch(63.1% 0.179 21.1)

  7. Step 600

    600

    #CC2D3D

    oklch(55.6% 0.194 21.4)

  8. Step 700

    700 (this color)

    #B21F31

    oklch(49.7% 0.18 21.3)

  9. Step 800

    800

    #8F1C28

    oklch(42.7% 0.149 21.3)

  10. Step 900

    900

    #731F25

    oklch(37.7% 0.117 20.9)

  11. Step 950

    950

    #441416

    oklch(27% 0.074 21.1)

Export this scale for Tailwind in the Tailwind colors tool

#B21F31 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)#4E48300.199
Deuteranopia (no green cones)#72672C0.181
Tritanopia (no blue cones)#C400280.036
Achromatopsia (no color)#5C5C5C0.182

Harmonies

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

Complementary

The opposite hue (180°).

  • #B21F31

    #B21F31

    oklch(49.7% 0.18 21.3)

  • #007076

    #007076

    oklch(49.6% 0.084 201.3)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #B21F31

    #B21F31

    oklch(49.7% 0.18 21.3)

  • #A7236E

    #A7236E

    oklch(49.6% 0.18 351.3)

  • #994800

    #994800

    oklch(49.6% 0.128 51.6)

Open the analogous palette in the generator

Split complementary

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

  • #B21F31

    #B21F31

    oklch(49.7% 0.18 21.3)

  • #00745B

    #00745B

    oklch(49.8% 0.097 171)

  • #006B91

    #006B91

    oklch(49.6% 0.101 231.8)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #B21F31

    #B21F31

    oklch(49.7% 0.18 21.3)

  • #157700

    #157700

    oklch(49.6% 0.164 141.3)

  • #1F5AC7

    #1F5AC7

    oklch(49.7% 0.181 261.4)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #B21F31

    #B21F31

    oklch(49.7% 0.18 21.3)

  • #656700

    #656700

    oklch(49.5% 0.109 111.1)

  • #007076

    #007076

    oklch(49.6% 0.084 201.3)

  • #6745BE

    #6745BE

    oklch(49.6% 0.18 291.3)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #B21F31, closest first.

Similar named colors

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

Use #B21F31 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.