#42D581
Closest named color: Seaweed (#18D17B). oklch(77.6% 0.172 153.8), rgb(66, 213, 129).
Aa
Black text reads best on this color (11.06:1).
About this color
#42D581 is a medium-light, vivid green. In OKLCH its lightness is 78%, its chroma 0.172 and its hue 154°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Seaweed (#18D17B), ΔE 0.021 away. Black text reads best on it, at 11.06:1.
| Hue family | Greens |
| Lightness | medium-light (78%) |
| Chroma | vivid (0.172) |
| Temperature | in between |
| Nearest name | Seaweed (#18D17B) |
| Black text | 11.06:1 |
| White text | 1.89:1 |
Values
| HEX | #42D581 |
| RGB | rgb(66, 213, 129) |
| HSL | hsl(146, 64%, 55%) |
| OKLCH | oklch(77.6% 0.172 153.8) |
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 #42D581 | 1.89:1 | Fails | Lc -39.9 | Non-text elements, placeholder text |
| Black text on #42D581 | 11.06:1 | AAA | Lc 68.2 | Content text, not long reading |
| #42D581 text on white | 1.89:1 | Fails | Lc 35.7 | Non-text elements, placeholder text |
| #42D581 text on black | 11.06:1 | AAA | Lc -66.8 | Content text, not long reading |
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 300.
-
Step 50
50
#EAFAEE
oklch(97% 0.023 153.5)
-
Step 100
100
#D1F4DB
oklch(93.5% 0.049 154.3)
-
Step 200
200
#A7ECBC
oklch(88.4% 0.096 153.7)
-
Step 300
300 (this color)
#42D581
oklch(77.6% 0.172 153.8)
-
Step 400
400
#00BF6A
oklch(70.6% 0.178 154)
-
Step 500
500
#00A45A
oklch(63.1% 0.159 153.9)
-
Step 600
600
#008A4B
oklch(55.6% 0.14 154)
-
Step 700
700
#00743E
oklch(49% 0.124 153.9)
-
Step 800
800
#005F32
oklch(42.6% 0.107 154.1)
-
Step 900
900
#005028
oklch(37.8% 0.097 153.4)
-
Step 950
950
#003016
oklch(27.1% 0.069 153.7)
#42D581 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) | #D5C47B | 0.151 |
| Deuteranopia (no green cones) | #C3B787 | 0.148 |
| Tritanopia (no blue cones) | #00D2C0 | 0.088 |
| Achromatopsia (no color) | #BCBCBC | 0.173 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42D581
#42D581
oklch(77.6% 0.172 153.8)
- #F688E3
#F688E3
oklch(77.5% 0.172 333.8)
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 #42D581, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Seaweed #18D17B ΔE 0.021
- Aqua Green #12E193 ΔE 0.033
- Emerald #06D6A0 ΔE 0.039
- Weird Green #3AE57F ΔE 0.046
- Soft Green #6FC276 ΔE 0.054
- Fresh Green #69D84F ΔE 0.056
- Algae Green #21C36F ΔE 0.056
- Dark Mint #48C072 ΔE 0.057
Use #42D581 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.