#66C351
Closest named color: Turtle Green (#75B84F). oklch(73.5% 0.176 140.1), rgb(102, 195, 81).
Aa
Black text reads best on this color (9.48:1).
About this color
#66C351 is a medium-light, vivid green. In OKLCH its lightness is 73%, its chroma 0.176 and its hue 140°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Turtle Green (#75B84F), ΔE 0.032 away. Black text reads best on it, at 9.48:1.
| Hue family | Greens |
| Lightness | medium-light (73%) |
| Chroma | vivid (0.176) |
| Temperature | in between |
| Nearest name | Turtle Green (#75B84F) |
| Black text | 9.48:1 |
| White text | 2.21:1 |
Values
| HEX | #66C351 |
| RGB | rgb(102, 195, 81) |
| HSL | hsl(109, 49%, 54%) |
| OKLCH | oklch(73.5% 0.176 140.1) |
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 #66C351 | 2.21:1 | Fails | Lc -48.1 | Large or bold text, headings |
| Black text on #66C351 | 9.48:1 | AAA | Lc 60.6 | Content text, not long reading |
| #66C351 text on white | 2.21:1 | Fails | Lc 43.3 | Non-text elements, placeholder text |
| #66C351 text on black | 9.48:1 | AAA | Lc -58.9 | 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 400.
-
Step 50
50
#F0F8EF
oklch(97.1% 0.015 142.2)
-
Step 100
100
#DFEFDC
oklch(93.5% 0.03 140.8)
-
Step 200
200
#C4E4BE
oklch(88.6% 0.061 140.7)
-
Step 300
300
#9AD28E
oklch(80.8% 0.11 140.1)
-
Step 400
400 (this color)
#66C351
oklch(73.5% 0.176 140.1)
-
Step 500
500
#31A500
oklch(63.2% 0.204 140.1)
-
Step 600
600
#288A00
oklch(55.5% 0.179 140)
-
Step 700
700
#207400
oklch(49% 0.158 140)
-
Step 800
800
#196000
oklch(42.8% 0.138 140)
-
Step 900
900
#135000
oklch(37.8% 0.122 140.1)
-
Step 950
950
#083000
oklch(27.1% 0.087 140)
#66C351 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) | #C8B345 | 0.121 |
| Deuteranopia (no green cones) | #BBAB5A | 0.120 |
| Tritanopia (no blue cones) | #5DBDAA | 0.118 |
| Achromatopsia (no color) | #AEAEAE | 0.177 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66C351
#66C351
oklch(73.5% 0.176 140.1)
- #D980ED
#D980ED
oklch(73.4% 0.177 320.1)
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 #66C351, closest first.
No curated palette has a color within ΔE 0.04 of #66C351.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Turtle Green #75B84F ΔE 0.032
- Apple #6ECB3C ΔE 0.032
- Dark Lime Green #7EBD01 ΔE 0.039
- Dark Mint #48C072 ΔE 0.042
- Leafy Green #51B73B ΔE 0.043
- Soft Green #6FC276 ΔE 0.044
- Algae Green #21C36F ΔE 0.044
- Dark Lime #84B701 ΔE 0.046
Use #66C351 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.