#66A751
Closest named color: Fern (#63A950). oklch(66.4% 0.137 138.5), rgb(102, 167, 81).
Aa
Black text reads best on this color (7.21:1).
About this color
#66A751 is a medium-light, moderately saturated green. In OKLCH its lightness is 66%, its chroma 0.137 and its hue 139°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Fern (#63A950), ΔE 0.007 away. Black text reads best on it, at 7.21:1.
| Hue family | Greens |
| Lightness | medium-light (66%) |
| Chroma | moderately saturated (0.137) |
| Temperature | in between |
| Nearest name | Fern (#63A950) |
| Black text | 7.21:1 |
| White text | 2.91:1 |
Values
| HEX | #66A751 |
| RGB | rgb(102, 167, 81) |
| HSL | hsl(105, 35%, 49%) |
| OKLCH | oklch(66.4% 0.137 138.5) |
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 #66A751 | 2.91:1 | Fails | Lc -60.6 | Content text, not long reading |
| Black text on #66A751 | 7.21:1 | AAA | Lc 48.7 | Large or bold text, headings |
| #66A751 text on white | 2.91:1 | Fails | Lc 55.3 | Large or bold text, headings |
| #66A751 text on black | 7.21:1 | AAA | Lc -46.5 | Large or bold text, headings |
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 500.
-
Step 50
50
#F2F7F1
oklch(97.1% 0.01 140.5)
-
Step 100
100
#E4EDE1
oklch(93.6% 0.019 137.8)
-
Step 200
200
#CDDFC8
oklch(88.4% 0.037 138.9)
-
Step 300
300
#ABCCA2
oklch(81% 0.068 139)
-
Step 400
400
#7EB16F
oklch(70.8% 0.107 138.7)
-
Step 500
500 (this color)
#66A751
oklch(66.4% 0.137 138.5)
-
Step 600
600
#408726
oklch(55.7% 0.149 138.6)
-
Step 700
700
#327218
oklch(49.1% 0.138 138.5)
-
Step 800
800
#2A5D17
oklch(42.7% 0.115 138.6)
-
Step 900
900
#274C1A
oklch(37.6% 0.089 138.4)
-
Step 950
950
#172D10
oklch(27% 0.058 138.6)
#66A751 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) | #AC9B49 | 0.092 |
| Deuteranopia (no green cones) | #A29557 | 0.092 |
| Tritanopia (no blue cones) | #62A293 | 0.093 |
| Achromatopsia (no color) | #979797 | 0.137 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66A751
#66A751
oklch(66.4% 0.137 138.5)
- #B776C9
#B776C9
oklch(66.4% 0.138 318.7)
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 #66A751, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Fern #63A950 ΔE 0.007
- Off Green #6BA353 ΔE 0.013
- Dark Pastel Green #56AE57 ΔE 0.022
- Muted Green #5FA052 ΔE 0.023
- Asparagus #77AB56 ΔE 0.024
- Mid Green #50A747 ΔE 0.025
- Algae #54AC68 ΔE 0.027
- Flat Green #699D4C ΔE 0.028
Use #66A751 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.