#283F37
Closest named color: Onyx (#343A40). oklch(34.6% 0.032 170.6), rgb(40, 63, 55).
Aa
White text reads best on this color (11.31:1).
About this color
#283F37 is a dark, muted teal or cyan. In OKLCH its lightness is 35%, its chroma 0.032 and its hue 171°. Its hue sits on the cool side of the wheel. The nearest named color is Onyx (#343A40), ΔE 0.032 away. White text reads best on it, at 11.31:1.
| Hue family | Teals and cyans |
| Lightness | dark (35%) |
| Chroma | muted (0.032) |
| Temperature | cool |
| Nearest name | Onyx (#343A40) |
| Black text | 1.85:1 |
| White text | 11.31:1 |
Values
| HEX | #283F37 |
| RGB | rgb(40, 63, 55) |
| HSL | hsl(159, 22%, 20%) |
| OKLCH | oklch(34.6% 0.032 170.6) |
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 #283F37 | 11.31:1 | AAA | Lc -99.8 | Preferred for body text |
| Black text on #283F37 | 1.85:1 | Fails | Lc 7.8 | Not readable |
| #283F37 text on white | 11.31:1 | AAA | Lc 96.1 | Preferred for body text |
| #283F37 text on black | 1.85:1 | Fails | Lc 0.0 | Not readable |
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 900.
-
Step 50
50
#F3F6F5
oklch(97.1% 0.003 174.5)
-
Step 100
100
#E5EBE9
oklch(93.5% 0.007 174.4)
-
Step 200
200
#D1DCD8
oklch(88.5% 0.013 172.3)
-
Step 300
300
#B2C6BE
oklch(80.9% 0.024 169.7)
-
Step 400
400
#89A99D
oklch(70.7% 0.039 170.4)
-
Step 500
500
#6B9485
oklch(63.2% 0.051 170)
-
Step 600
600
#527E6F
oklch(55.6% 0.054 170.8)
-
Step 700
700
#436A5D
oklch(49.1% 0.049 171.2)
-
Step 800
800
#37574C
oklch(42.8% 0.042 170.6)
-
Step 900
900 (this color)
#283F37
oklch(34.6% 0.032 170.6)
-
Step 950
950
#1C2A25
oklch(27% 0.021 170.6)
#283F37 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) | #3E3C37 | 0.034 |
| Deuteranopia (no green cones) | #3A3938 | 0.033 |
| Tritanopia (no blue cones) | #223F3D | 0.012 |
| Achromatopsia (no color) | #3A3A3A | 0.032 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283F37
#283F37
oklch(34.6% 0.032 170.6)
- #47333C
#47333C
oklch(34.7% 0.032 350.2)
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 #283F37, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Onyx #343A40 ΔE 0.032
- Charcoal Grey #3C4142 ΔE 0.037
- Dark Blue Grey #1F3B4D ΔE 0.046
- Charcoal #264653 ΔE 0.047
- Pakistan Green #283618 ΔE 0.049
- Evergreen #05472A ΔE 0.049
- Midnight Green #073B4C ΔE 0.051
- Dark Teal #014D4E ΔE 0.052
Use #283F37 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.