#283A42
Closest named color: Onyx (#343A40). oklch(33.6% 0.027 227.2), rgb(40, 58, 66).
Aa
White text reads best on this color (11.83:1).
About this color
#283A42 is a dark close to neutral grey. In OKLCH its lightness is 34%, its chroma 0.027. It has too little chroma to lean warm or cool. The nearest named color is Onyx (#343A40), ΔE 0.018 away. White text reads best on it, at 11.83:1.
| Hue family | Neutrals |
| Lightness | dark (34%) |
| Chroma | close to neutral grey (0.027) |
| Temperature | neutral |
| Nearest name | Onyx (#343A40) |
| Black text | 1.77:1 |
| White text | 11.83:1 |
Values
| HEX | #283A42 |
| RGB | rgb(40, 58, 66) |
| HSL | hsl(198, 25%, 21%) |
| OKLCH | oklch(33.6% 0.027 227.2) |
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 #283A42 | 11.83:1 | AAA | Lc -100.7 | Preferred for body text |
| Black text on #283A42 | 1.77:1 | Fails | Lc 0.0 | Not readable |
| #283A42 text on white | 11.83:1 | AAA | Lc 97.1 | Preferred for body text |
| #283A42 text on black | 1.77:1 | 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
#F4F6F7
oklch(97.2% 0.003 228.8)
-
Step 100
100
#E6EBED
oklch(93.7% 0.006 223.5)
-
Step 200
200
#D2DBDF
oklch(88.6% 0.011 226)
-
Step 300
300
#B4C4CB
oklch(81% 0.02 225.8)
-
Step 400
400
#8CA5B1
oklch(70.7% 0.033 228.4)
-
Step 500
500
#6F8F9D
oklch(63.1% 0.042 226.5)
-
Step 600
600
#577988
oklch(55.6% 0.045 227.1)
-
Step 700
700
#476673
oklch(49.1% 0.042 225.9)
-
Step 800
800
#3B535E
oklch(42.7% 0.034 228)
-
Step 900
900 (this color)
#283A42
oklch(33.6% 0.027 227.2)
-
Step 950
950
#1E282D
oklch(27% 0.017 229.8)
#283A42 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) | #363942 | 0.021 |
| Deuteranopia (no green cones) | #323642 | 0.019 |
| Tritanopia (no blue cones) | #1F3C3C | 0.019 |
| Achromatopsia (no color) | #373737 | 0.027 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283A42
#283A42
oklch(33.6% 0.027 227.2)
- #43332B
#43332B
oklch(33.6% 0.027 47.9)
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 #283A42, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Onyx #343A40 ΔE 0.018
- Dark Blue Grey #1F3B4D ΔE 0.021
- Gunmetal #293241 ΔE 0.027
- Midnight Green #073B4C ΔE 0.032
- Charcoal Grey #3C4142 ΔE 0.040
- Charcoal #264653 ΔE 0.042
- Space Cadet #2B2D42 ΔE 0.044
- Prussian Blue #1D3557 ΔE 0.047
Use #283A42 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.