#666E21
Closest named color: Browny Green (#6F6C0A). oklch(51.5% 0.1 115.1), rgb(102, 110, 33).
Aa
White text reads best on this color (5.50:1).
About this color
#666E21 is a medium-dark, moderately saturated yellow. In OKLCH its lightness is 52%, its chroma 0.100 and its hue 115°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Browny Green (#6F6C0A), ΔE 0.016 away. White text reads best on it, at 5.50:1.
| Hue family | Yellows |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.100) |
| Temperature | in between |
| Nearest name | Browny Green (#6F6C0A) |
| Black text | 3.81:1 |
| White text | 5.50:1 |
Values
| HEX | #666E21 |
| RGB | rgb(102, 110, 33) |
| HSL | hsl(66, 54%, 28%) |
| OKLCH | oklch(51.5% 0.1 115.1) |
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 #666E21 | 5.50:1 | AA | Lc -82.7 | Fine for body text |
| Black text on #666E21 | 3.81:1 | AA large text | Lc 26.7 | Dividers and decoration only |
| #666E21 text on white | 5.50:1 | AA | Lc 77.4 | Fine for body text |
| #666E21 text on black | 3.81:1 | AA large text | Lc -24.4 | 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
#F5F6F1
oklch(97.1% 0.007 115.7)
-
Step 100
100
#E9EBE1
oklch(93.6% 0.013 115.8)
-
Step 200
200
#D8DCC8
oklch(88.6% 0.027 116.1)
-
Step 300
300
#BFC5A2
oklch(80.9% 0.048 115.4)
-
Step 400
400
#9FA76E
oklch(70.8% 0.078 114.9)
-
Step 500
500
#879047
oklch(63% 0.098 115.1)
-
Step 600
600
#727A26
oklch(55.6% 0.107 114.6)
-
Step 700
700 (this color)
#666E21
oklch(51.5% 0.1 115.1)
-
Step 800
800
#4E5417
oklch(42.7% 0.083 114.8)
-
Step 900
900
#40451A
oklch(37.5% 0.064 115.1)
-
Step 950
950
#262910
oklch(27.1% 0.041 114.9)
#666E21 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) | #766816 | 0.028 |
| Deuteranopia (no green cones) | #766A27 | 0.029 |
| Tritanopia (no blue cones) | #6D675E | 0.088 |
| Achromatopsia (no color) | #696969 | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #666E21
#666E21
oklch(51.5% 0.1 115.1)
- #6C5B9B
#6C5B9B
oklch(51.6% 0.1 294.9)
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 #666E21, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Browny Green #6F6C0A ΔE 0.016
- Brown Green #706C11 ΔE 0.016
- Muddy Green #657432 ΔE 0.020
- Dark Moss Green #606C38 ΔE 0.026
- Mud Green #606602 ΔE 0.029
- Dark Olive Green #556B2F ΔE 0.029
- Greeny Brown #696006 ΔE 0.039
- Murky Green #6C7A0E ΔE 0.041
Use #666E21 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.