#178A31
Closest named color: Forest Green (#228B22). oklch(55.4% 0.16 146.1), rgb(23, 138, 49).
Aa
Black text reads best on this color (4.71:1).
About this color
#178A31 is a medium-dark, vivid green. In OKLCH its lightness is 55%, its chroma 0.160 and its hue 146°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Forest Green (#228B22), ΔE 0.013 away. Black text reads best on it, at 4.71:1.
| Hue family | Greens |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.160) |
| Temperature | in between |
| Nearest name | Forest Green (#228B22) |
| Black text | 4.71:1 |
| White text | 4.45:1 |
Values
| HEX | #178A31 |
| RGB | rgb(23, 138, 49) |
| HSL | hsl(134, 71%, 32%) |
| OKLCH | oklch(55.4% 0.16 146.1) |
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 #178A31 | 4.45:1 | AA large text | Lc -75.8 | Fine for body text |
| Black text on #178A31 | 4.71:1 | AA | Lc 33.7 | Non-text elements, placeholder text |
| #178A31 text on white | 4.45:1 | AA large text | Lc 70.4 | Content text, not long reading |
| #178A31 text on black | 4.71:1 | AA | Lc -31.3 | 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
#F2F7F2
oklch(97.1% 0.008 145.5)
-
Step 100
100
#E1EEE2
oklch(93.6% 0.021 147.6)
-
Step 200
200
#C9E1CA
oklch(88.6% 0.04 146.4)
-
Step 300
300
#A3CEA5
oklch(81% 0.073 146.1)
-
Step 400
400
#6FB474
oklch(70.7% 0.116 145.9)
-
Step 500
500
#43A04F
oklch(63% 0.147 146)
-
Step 600
600 (this color)
#178A31
oklch(55.4% 0.16 146.1)
-
Step 700
700
#027524
oklch(49% 0.148 146.2)
-
Step 800
800
#0D601F
oklch(42.8% 0.124 145.9)
-
Step 900
900
#174E1F
oklch(37.6% 0.095 145.9)
-
Step 950
950
#0F2E13
oklch(27% 0.061 146.2)
#178A31 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) | #8C7D27 | 0.121 |
| Deuteranopia (no green cones) | #807439 | 0.122 |
| Tritanopia (no blue cones) | #008777 | 0.096 |
| Achromatopsia (no color) | #777777 | 0.161 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178A31
#178A31
oklch(55.4% 0.16 146.1)
- #A14BA4
#A14BA4
oklch(55.5% 0.16 326.2)
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 #178A31, closest first.
No curated palette has a color within ΔE 0.04 of #178A31.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Forest Green #228B22 ΔE 0.013
- Emerald Green #028F1E ΔE 0.024
- Kelley Green #009337 ΔE 0.026
- Dark Grass Green #388004 ΔE 0.033
- Tree Green #2A7E19 ΔE 0.035
- Irish Green #019529 ΔE 0.036
- Jungle Green #048243 ΔE 0.036
- Green #008000 ΔE 0.040
Use #178A31 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.