#178B66
Closest named color: Viridian (#1E9167). oklch(56.7% 0.113 165.3), rgb(23, 139, 102).
Aa
Black text reads best on this color (4.92:1).
About this color
#178B66 is a medium-dark, moderately saturated green. In OKLCH its lightness is 57%, its chroma 0.113 and its hue 165°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Viridian (#1E9167), ΔE 0.019 away. Black text reads best on it, at 4.92:1.
| Hue family | Greens |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.113) |
| Temperature | in between |
| Nearest name | Viridian (#1E9167) |
| Black text | 4.92:1 |
| White text | 4.26:1 |
Values
| HEX | #178B66 |
| RGB | rgb(23, 139, 102) |
| HSL | hsl(161, 72%, 32%) |
| OKLCH | oklch(56.7% 0.113 165.3) |
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 #178B66 | 4.26:1 | AA large text | Lc -74.5 | Content text, not long reading |
| Black text on #178B66 | 4.92:1 | AA | Lc 35.0 | Non-text elements, placeholder text |
| #178B66 text on white | 4.26:1 | AA large text | Lc 69.0 | Content text, not long reading |
| #178B66 text on black | 4.92:1 | AA | Lc -32.6 | 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
#F1F7F4
oklch(97.1% 0.007 164.9)
-
Step 100
100
#E1EDE7
oklch(93.5% 0.015 164.7)
-
Step 200
200
#C9DFD5
oklch(88.4% 0.027 166.7)
-
Step 300
300
#A3CCB9
oklch(81% 0.051 165.2)
-
Step 400
400
#6EB194
oklch(70.7% 0.081 165)
-
Step 500
500
#409D7A
oklch(63% 0.104 165.4)
-
Step 600
600 (this color)
#178B66
oklch(56.7% 0.113 165.3)
-
Step 700
700
#007352
oklch(49.2% 0.104 164.9)
-
Step 800
800
#075E43
oklch(42.8% 0.088 164.9)
-
Step 900
900
#154D39
oklch(37.8% 0.068 165.4)
-
Step 950
950
#0E2D21
oklch(27% 0.043 165.1)
#178B66 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) | #888064 | 0.112 |
| Deuteranopia (no green cones) | #7A7668 | 0.108 |
| Tritanopia (no blue cones) | #008B81 | 0.041 |
| Achromatopsia (no color) | #7A7A7A | 0.114 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178B66
#178B66
oklch(56.7% 0.113 165.3)
- #A55985
#A55985
oklch(56.7% 0.113 345.6)
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 #178B66, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Viridian #1E9167 ΔE 0.019
- Sea Green #2E8B57 ΔE 0.022
- Dark Sage #598556 ΔE 0.047
- Light Forest Green #4F9153 ΔE 0.049
- Jungle Green #048243 ΔE 0.050
- Ocean Green #3D9973 ΔE 0.051
- Dark Cyan #008B8B ΔE 0.056
- Fern Green #548D44 ΔE 0.057
Use #178B66 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.