#278B4E
Closest named color: Sea Green (#2E8B57). oklch(56.5% 0.13 152.2), rgb(39, 139, 78).
Aa
Black text reads best on this color (4.88:1).
About this color
#278B4E is a medium-dark, moderately saturated green. In OKLCH its lightness is 56%, its chroma 0.130 and its hue 152°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Sea Green (#2E8B57), ΔE 0.014 away. Black text reads best on it, at 4.88:1.
| Hue family | Greens |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.130) |
| Temperature | in between |
| Nearest name | Sea Green (#2E8B57) |
| Black text | 4.88:1 |
| White text | 4.29:1 |
Values
| HEX | #278B4E |
| RGB | rgb(39, 139, 78) |
| HSL | hsl(143, 56%, 35%) |
| OKLCH | oklch(56.5% 0.13 152.2) |
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 #278B4E | 4.29:1 | AA large text | Lc -74.8 | Content text, not long reading |
| Black text on #278B4E | 4.88:1 | AA | Lc 34.8 | Non-text elements, placeholder text |
| #278B4E text on white | 4.29:1 | AA large text | Lc 69.3 | Content text, not long reading |
| #278B4E text on black | 4.88:1 | AA | Lc -32.3 | Non-text elements, placeholder text |
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 600.
-
Step 50
50
#F2F7F3
oklch(97.1% 0.007 151.9)
-
Step 100
100
#E2EDE4
oklch(93.5% 0.017 151.1)
-
Step 200
200
#CAE0CF
oklch(88.6% 0.033 152.4)
-
Step 300
300
#A5CCAE
oklch(80.9% 0.059 151.9)
-
Step 400
400
#72B284
oklch(70.8% 0.094 152.3)
-
Step 500
500
#499E65
oklch(63.1% 0.119 152.3)
-
Step 600
600 (this color)
#278B4E
oklch(56.5% 0.13 152.2)
-
Step 700
700
#13733C
oklch(49% 0.121 152.1)
-
Step 800
800
#155E32
oklch(42.7% 0.101 152.1)
-
Step 900
900
#1A4D2C
oklch(37.6% 0.078 152.2)
-
Step 950
950
#112D1A
oklch(26.9% 0.049 152.2)
#278B4E 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) | #8B7F4A | 0.111 |
| Deuteranopia (no green cones) | #7F7752 | 0.109 |
| Tritanopia (no blue cones) | #00897C | 0.068 |
| Achromatopsia (no color) | #7A7A7A | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #278B4E
#278B4E
oklch(56.5% 0.13 152.2)
- #A15697
#A15697
oklch(56.5% 0.13 332.3)
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 #278B4E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sea Green #2E8B57 ΔE 0.014
- Viridian #1E9167 ΔE 0.033
- Jungle Green #048243 ΔE 0.033
- Fern Green #548D44 ΔE 0.037
- Light Forest Green #4F9153 ΔE 0.038
- Kelley Green #009337 ΔE 0.043
- Forest Green #228B22 ΔE 0.046
- Dark Sage #598556 ΔE 0.048
Use #278B4E 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.