#646E51
Closest named color: Dark Moss Green (#606C38). oklch(52.1% 0.045 123.4), rgb(100, 110, 81).
Aa
White text reads best on this color (5.39:1).
About this color
#646E51 is a medium-dark, muted yellow. In OKLCH its lightness is 52%, its chroma 0.045 and its hue 123°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Dark Moss Green (#606C38), ΔE 0.034 away. White text reads best on it, at 5.39:1.
| Hue family | Yellows |
| Lightness | medium-dark (52%) |
| Chroma | muted (0.045) |
| Temperature | in between |
| Nearest name | Dark Moss Green (#606C38) |
| Black text | 3.89:1 |
| White text | 5.39:1 |
Values
| HEX | #646E51 |
| RGB | rgb(100, 110, 81) |
| HSL | hsl(81, 15%, 37%) |
| OKLCH | oklch(52.1% 0.045 123.4) |
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.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #646E51 | 5.39:1 | AA | Lc -82.2 | Fine for body text |
| Black text on #646E51 | 3.89:1 | AA large text | Lc 27.2 | Dividers and decoration only |
| #646E51 text on white | 5.39:1 | AA | Lc 76.9 | Fine for body text |
| #646E51 text on black | 3.89:1 | AA large text | Lc -24.8 | 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.
-
Step 50
50
#F5F6F4
oklch(97.2% 0.003 128.5)
-
Step 100
100
#E9EBE6
oklch(93.7% 0.007 124.5)
-
Step 200
200
#D7DBD2
oklch(88.6% 0.013 126.4)
-
Step 300
300
#BEC3B4
oklch(80.9% 0.021 121.9)
-
Step 400
400
#9CA58D
oklch(70.8% 0.035 124.1)
-
Step 500
500
#848E70
oklch(63% 0.045 122.7)
-
Step 600
600
#6D7859
oklch(55.5% 0.048 123.8)
-
Step 700
700 (this color)
#646E51
oklch(52.1% 0.045 123.4)
-
Step 800
800
#4B533C
oklch(42.8% 0.038 123.6)
-
Step 900
900
#3E4433
oklch(37.6% 0.029 123.6)
-
Step 950
950
#25281E
oklch(27% 0.018 121.2)
#646E51 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.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #716A4F | 0.022 |
| Deuteranopia (no green cones) | #706A52 | 0.021 |
| Tritanopia (no blue cones) | #666B66 | 0.036 |
| Achromatopsia (no color) | #6A6A6A | 0.045 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646E51
#646E51
oklch(52.1% 0.045 123.4)
- #6F637F
#6F637F
oklch(52.1% 0.046 304.4)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #646E51, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Moss Green #606C38 ΔE 0.034
- Grey Brown #7F7053 ΔE 0.043
- Dark Taupe #7F684E ΔE 0.044
- Dim Gray #696969 ΔE 0.045
- Muddy Green #657432 ΔE 0.048
- Dark Olive Green #556B2F ΔE 0.051
- Dirt Brown #836539 ΔE 0.054
- Dull Brown #876E4B ΔE 0.055
Use #646E51 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.