#663F17

Closest named color: Mud Brown (#60460F). oklch(40.6% 0.077 63), rgb(102, 63, 23).

Aa

White text reads best on this color (9.17:1).

About this color

#663F17 is a dark, moderately saturated brown. In OKLCH its lightness is 41%, its chroma 0.077 and its hue 63°. Its hue sits on the warm side of the wheel. The nearest named color is Mud Brown (#60460F), ΔE 0.025 away. White text reads best on it, at 9.17:1.

Hue familyBrowns
Lightnessdark (41%)
Chromamoderately saturated (0.077)
Temperaturewarm
Nearest nameMud Brown (#60460F)
Black text2.28:1
White text9.17:1

Values

HEX#663F17
RGBrgb(102, 63, 23)
HSLhsl(30, 63%, 25%)
OKLCHoklch(40.6% 0.077 63)

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 #663F17 9.17:1 AAA Lc -95.3 Preferred for body text
Black text on #663F17 2.28:1 Fails Lc 13.0 Not readable
#663F17 text on white 9.17:1 AAA Lc 90.9 Preferred for body text
#663F17 text on black 2.28:1 Fails Lc -11.4 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 800.

  1. Step 50

    50

    #F8F5F1

    oklch(97.1% 0.006 75.4)

  2. Step 100

    100

    #F0E8E1

    oklch(93.5% 0.013 63.9)

  3. Step 200

    200

    #E5D6C9

    oklch(88.5% 0.024 63.5)

  4. Step 300

    300

    #D6BBA3

    oklch(80.9% 0.045 63.8)

  5. Step 400

    400

    #C19772

    oklch(70.7% 0.072 62.6)

  6. Step 500

    500

    #B17D4C

    oklch(63.2% 0.092 63.2)

  7. Step 600

    600

    #9C652F

    oklch(55.6% 0.099 62.6)

  8. Step 700

    700

    #855421

    oklch(49.1% 0.092 63.4)

  9. Step 800

    800 (this color)

    #663F17

    oklch(40.6% 0.077 63)

  10. Step 900

    900

    #583A1E

    oklch(37.7% 0.06 62.4)

  11. Step 950

    950

    #342212

    oklch(27% 0.038 61.7)

Export this scale for Tailwind in the Tailwind colors tool

#663F17 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)#4B42120.053
Deuteranopia (no green cones)#544B180.046
Tritanopia (no blue cones)#7036370.058
Achromatopsia (no color)#4848480.077

Harmonies

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

Complementary

The opposite hue (180°).

  • #663F17

    #663F17

    oklch(40.6% 0.077 63)

  • #1E4D6F

    #1E4D6F

    oklch(40.5% 0.077 243.3)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #663F17

    #663F17

    oklch(40.6% 0.077 63)

  • #6C382D

    #6C382D

    oklch(40.4% 0.077 33)

  • #57480C

    #57480C

    oklch(40.6% 0.077 93.9)

Open the analogous palette in the generator

Split complementary

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

  • #663F17

    #663F17

    oklch(40.6% 0.077 63)

  • #005360

    #005360

    oklch(40.6% 0.071 212.8)

  • #3C4673

    #3C4673

    oklch(40.7% 0.077 273.1)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #663F17

    #663F17

    oklch(40.6% 0.077 63)

  • #00564D

    #00564D

    oklch(40.7% 0.073 182.8)

  • #523E6B

    #523E6B

    oklch(40.5% 0.077 303.6)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #663F17

    #663F17

    oklch(40.6% 0.077 63)

  • #235535

    #235535

    oklch(40.6% 0.077 153.2)

  • #1E4D6F

    #1E4D6F

    oklch(40.5% 0.077 243.3)

  • #62395B

    #62395B

    oklch(40.7% 0.076 333.3)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #663F17, closest first.

Similar named colors

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

Use #663F17 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.