#B51A37

Closest named color: Rose Red (#BE013C). oklch(50% 0.186 18.6), rgb(181, 26, 55).

Aa

White text reads best on this color (6.62:1).

About this color

#B51A37 is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.186 and its hue 19°. Its hue sits on the warm side of the wheel. The nearest named color is Rose Red (#BE013C), ΔE 0.022 away. White text reads best on it, at 6.62:1.

Hue familyReds
Lightnessmedium-dark (50%)
Chromavivid (0.186)
Temperaturewarm
Nearest nameRose Red (#BE013C)
Black text3.16:1
White text6.62:1

Values

HEX#B51A37
RGBrgb(181, 26, 55)
HSLhsl(349, 75%, 41%)
OKLCHoklch(50% 0.186 18.6)

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 #B51A37 6.62:1 AA Lc -86.1 Fine for body text
Black text on #B51A37 3.16:1 AA large text Lc 23.1 Dividers and decoration only
#B51A37 text on white 6.62:1 AA Lc 80.9 Fine for body text
#B51A37 text on black 3.16:1 AA large text Lc -20.9 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

    #FEF2F2

    oklch(97.1% 0.013 17.4)

  2. Step 100

    100

    #FBE3E3

    oklch(93.5% 0.026 17.6)

  3. Step 200

    200

    #F9CDCC

    oklch(88.6% 0.05 19.7)

  4. Step 300

    300

    #F5A9AA

    oklch(80.8% 0.09 18.4)

  5. Step 400

    400

    #EC787D

    oklch(70.7% 0.143 18.7)

  6. Step 500

    500

    #E34E5C

    oklch(63.1% 0.184 18.8)

  7. Step 600

    600

    #CE2743

    oklch(55.6% 0.2 18.5)

  8. Step 700

    700 (this color)

    #B51A37

    oklch(50% 0.186 18.6)

  9. Step 800

    800

    #90182C

    oklch(42.7% 0.153 18.6)

  10. Step 900

    900

    #741D27

    oklch(37.7% 0.12 18.9)

  11. Step 950

    950

    #441317

    oklch(26.9% 0.075 19)

Export this scale for Tailwind in the Tailwind colors tool

#B51A37 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)#4D48370.206
Deuteranopia (no green cones)#7368320.188
Tritanopia (no blue cones)#C700280.038
Achromatopsia (no color)#5D5D5D0.187

Harmonies

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

Complementary

The opposite hue (180°).

  • #B51A37

    #B51A37

    oklch(50% 0.186 18.6)

  • #007275

    #007275

    oklch(50.1% 0.085 198)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #B51A37

    #B51A37

    oklch(50% 0.186 18.6)

  • #A92174

    #A92174

    oklch(50.1% 0.186 348.9)

  • #9E4600

    #9E4600

    oklch(50.1% 0.135 48.8)

Open the analogous palette in the generator

Split complementary

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

  • #B51A37

    #B51A37

    oklch(50% 0.186 18.6)

  • #007559

    #007559

    oklch(50% 0.1 168.8)

  • #006D8F

    #006D8F

    oklch(50% 0.098 228.4)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #B51A37

    #B51A37

    oklch(50% 0.186 18.6)

  • #2A7700

    #2A7700

    oklch(50.1% 0.157 138.7)

  • #065CCA

    #065CCA

    oklch(50% 0.186 258.6)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #B51A37

    #B51A37

    oklch(50% 0.186 18.6)

  • #696700

    #696700

    oklch(49.9% 0.108 108.4)

  • #007275

    #007275

    oklch(50.1% 0.085 198)

  • #6447C4

    #6447C4

    oklch(50.1% 0.185 288.5)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #B51A37, closest first.

Similar named colors

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

Use #B51A37 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.