#178A39
Closest named color: Forest Green (#228B22). oklch(55.5% 0.153 147.7), rgb(23, 138, 57).
Aa
Black text reads best on this color (4.73:1).
About this color
#178A39 is a medium-dark, vivid green. In OKLCH its lightness is 56%, its chroma 0.153 and its hue 148°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Forest Green (#228B22), ΔE 0.021 away. Black text reads best on it, at 4.73:1.
| Hue family | Greens |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.153) |
| Temperature | in between |
| Nearest name | Forest Green (#228B22) |
| Black text | 4.73:1 |
| White text | 4.43:1 |
Values
| HEX | #178A39 |
| RGB | rgb(23, 138, 57) |
| HSL | hsl(138, 71%, 32%) |
| OKLCH | oklch(55.5% 0.153 147.7) |
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 #178A39 | 4.43:1 | AA large text | Lc -75.8 | Fine for body text |
| Black text on #178A39 | 4.73:1 | AA | Lc 33.8 | Non-text elements, placeholder text |
| #178A39 text on white | 4.43:1 | AA large text | Lc 70.3 | Content text, not long reading |
| #178A39 text on black | 4.73:1 | AA | Lc -31.4 | 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
#F2F7F2
oklch(97.1% 0.008 145.5)
-
Step 100
100
#E1EEE2
oklch(93.6% 0.021 147.6)
-
Step 200
200
#C9E1CB
oklch(88.6% 0.039 147.6)
-
Step 300
300
#A3CDA8
oklch(80.8% 0.068 148.2)
-
Step 400
400
#6FB379
oklch(70.6% 0.109 147.9)
-
Step 500
500
#43A055
oklch(63.1% 0.141 147.6)
-
Step 600
600 (this color)
#178A39
oklch(55.5% 0.153 147.7)
-
Step 700
700
#02752B
oklch(49.1% 0.143 147.7)
-
Step 800
800
#0C5F25
oklch(42.6% 0.118 147.8)
-
Step 900
900
#164E23
oklch(37.6% 0.092 147.9)
-
Step 950
950
#0F2E15
oklch(27% 0.059 147.8)
#178A39 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) | #8C7D31 | 0.121 |
| Deuteranopia (no green cones) | #7F743F | 0.120 |
| Tritanopia (no blue cones) | #008778 | 0.089 |
| Achromatopsia (no color) | #787878 | 0.154 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178A39
#178A39
oklch(55.5% 0.153 147.7)
- #A14DA0
#A14DA0
oklch(55.6% 0.153 327.8)
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 #178A39, closest first.
No curated palette has a color within ΔE 0.04 of #178A39.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Forest Green #228B22 ΔE 0.021
- Kelley Green #009337 ΔE 0.028
- Jungle Green #048243 ΔE 0.031
- Emerald Green #028F1E ΔE 0.031
- Dark Grass Green #388004 ΔE 0.038
- Tree Green #2A7E19 ΔE 0.038
- Irish Green #019529 ΔE 0.040
- Sea Green #2E8B57 ΔE 0.041
Use #178A39 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.