#283B5E
Closest named color: Prussian Blue (#1D3557). oklch(35.4% 0.066 261.9), rgb(40, 59, 94).
Aa
White text reads best on this color (11.18:1).
About this color
#283B5E is a dark, muted blue. In OKLCH its lightness is 35%, its chroma 0.066 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.027 away. White text reads best on it, at 11.18:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | muted (0.066) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.87:1 |
| White text | 11.18:1 |
Values
| HEX | #283B5E |
| RGB | rgb(40, 59, 94) |
| HSL | hsl(219, 40%, 26%) |
| OKLCH | oklch(35.4% 0.066 261.9) |
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 #283B5E | 11.18:1 | AAA | Lc -99.5 | Preferred for body text |
| Black text on #283B5E | 1.87:1 | Fails | Lc 8.2 | Not readable |
| #283B5E text on white | 11.18:1 | AAA | Lc 95.7 | Preferred for body text |
| #283B5E text on black | 1.87:1 | 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
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E5EAF4
oklch(93.6% 0.015 264.5)
-
Step 200
200
#CFDAEC
oklch(88.5% 0.028 260.3)
-
Step 300
300
#AFC1E1
oklch(80.8% 0.05 262)
-
Step 400
400
#86A1D3
oklch(70.7% 0.08 262.5)
-
Step 500
500
#6789C7
oklch(63.1% 0.102 261.9)
-
Step 600
600
#4F72B4
oklch(55.6% 0.111 262.2)
-
Step 700
700
#405F9B
oklch(49.1% 0.103 262.5)
-
Step 800
800
#354E7D
oklch(42.7% 0.084 262.2)
-
Step 900
900 (this color)
#283B5E
oklch(35.4% 0.066 261.9)
-
Step 950
950
#1B263B
oklch(26.9% 0.042 262.7)
#283B5E 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) | #2D3E5F | 0.012 |
| Deuteranopia (no green cones) | #27395D | 0.007 |
| Tritanopia (no blue cones) | #0B4348 | 0.059 |
| Achromatopsia (no color) | #3B3B3B | 0.066 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283B5E
#283B5E
oklch(35.4% 0.066 261.9)
- #4D380A
#4D380A
oklch(35.5% 0.066 82.2)
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 #283B5E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.027
- Dark Blue Grey #1F3B4D ΔE 0.033
- Dark Grey Blue #29465B ΔE 0.037
- Marine Blue #01386A ΔE 0.041
- Charcoal #264653 ΔE 0.045
- Midnight Green #073B4C ΔE 0.046
- Twilight Blue #0A437A ΔE 0.052
- Gunmetal #293241 ΔE 0.053
Use #283B5E 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.