#283A40
Closest named color: Onyx (#343A40). oklch(33.5% 0.025 220.5), rgb(40, 58, 64).
Aa
White text reads best on this color (11.86:1).
About this color
#283A40 is a dark close to neutral grey. In OKLCH its lightness is 34%, its chroma 0.025. 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 11.86:1.
| Hue family | Neutrals |
| Lightness | dark (34%) |
| Chroma | close to neutral grey (0.025) |
| Temperature | neutral |
| Nearest name | Onyx (#343A40) |
| Black text | 1.76:1 |
| White text | 11.86:1 |
Values
| HEX | #283A40 |
| RGB | rgb(40, 58, 64) |
| HSL | hsl(195, 23%, 20%) |
| OKLCH | oklch(33.5% 0.025 220.5) |
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 #283A40 | 11.86:1 | AAA | Lc -100.8 | Preferred for body text |
| Black text on #283A40 | 1.76:1 | Fails | Lc 0.0 | Not readable |
| #283A40 text on white | 11.86:1 | AAA | Lc 97.2 | Preferred for body text |
| #283A40 text on black | 1.76:1 | 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
#E6EBEC
oklch(93.7% 0.006 211)
-
Step 200
200
#D2DBDE
oklch(88.5% 0.011 219.6)
-
Step 300
300
#B4C4C9
oklch(81% 0.019 218.4)
-
Step 400
400
#8CA5AE
oklch(70.6% 0.031 221.6)
-
Step 500
500
#708F9A
oklch(63% 0.039 221.6)
-
Step 600
600
#577985
oklch(55.5% 0.043 221.8)
-
Step 700
700
#476670
oklch(49% 0.039 219.9)
-
Step 800
800
#3B535C
oklch(42.6% 0.033 223.1)
-
Step 900
900 (this color)
#283A40
oklch(33.5% 0.025 220.5)
-
Step 950
950
#1E282C
oklch(26.9% 0.016 224.2)
#283A40 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) | #363940 | 0.021 |
| Deuteranopia (no green cones) | #333640 | 0.020 |
| Tritanopia (no blue cones) | #203C3C | 0.015 |
| Achromatopsia (no color) | #373737 | 0.026 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283A40
#283A40
oklch(33.5% 0.025 220.5)
- #43332D
#43332D
oklch(33.7% 0.026 41.5)
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 #283A40, 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 0.024
- Gunmetal #293241 ΔE 0.028
- Midnight Green #073B4C ΔE 0.034
- Charcoal Grey #3C4142 ΔE 0.040
- Charcoal #264653 ΔE 0.044
- Space Cadet #2B2D42 ΔE 0.045
- Prussian Blue #1D3557 ΔE 0.050
Use #283A40 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.