#284583
Closest named color: Cobalt (#1E488F). oklch(40.3% 0.11 263.4), rgb(40, 69, 131).
Aa
White text reads best on this color (9.25:1).
About this color
#284583 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.110 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.021 away. White text reads best on it, at 9.25:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.110) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.26:1 |
| White text | 9.25:1 |
Values
| HEX | #284583 |
| RGB | rgb(40, 69, 131) |
| HSL | hsl(221, 53%, 34%) |
| OKLCH | oklch(40.3% 0.11 263.4) |
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 #284583 | 9.25:1 | AAA | Lc -95.4 | Preferred for body text |
| Black text on #284583 | 2.26:1 | Fails | Lc 12.9 | Not readable |
| #284583 text on white | 9.25:1 | AAA | Lc 91.1 | Preferred for body text |
| #284583 text on black | 2.26:1 | Fails | Lc -11.3 | 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 800.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CDDAF1
oklch(88.6% 0.035 262)
-
Step 300
300
#ABC1EB
oklch(80.9% 0.064 263.3)
-
Step 400
400
#7FA0E1
oklch(70.7% 0.103 263.3)
-
Step 500
500
#5F87D9
oklch(63.1% 0.132 263.4)
-
Step 600
600
#466FC6
oklch(55.6% 0.143 263.5)
-
Step 700
700
#385CAB
oklch(49% 0.133 263.8)
-
Step 800
800 (this color)
#284583
oklch(40.3% 0.11 263.4)
-
Step 900
900
#29406F
oklch(37.8% 0.086 263.2)
-
Step 950
950
#182641
oklch(27.1% 0.054 262.5)
#284583 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) | #264C85 | 0.020 |
| Deuteranopia (no green cones) | #154382 | 0.019 |
| Tritanopia (no blue cones) | #00535D | 0.090 |
| Achromatopsia (no color) | #474747 | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #284583
#284583
oklch(40.3% 0.11 263.4)
- #5E4300
#5E4300
oklch(40.2% 0.083 82.4)
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 #284583, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.021
- Twilight Blue #0A437A ΔE 0.030
- Light Navy #155084 ΔE 0.033
- Dusk Blue #26538D ΔE 0.041
- Deep Sea Blue #015482 ΔE 0.047
- Dark Slate Blue #483D8B ΔE 0.050
- Blueberry #464196 ΔE 0.053
- Light Navy Blue #2E5A88 ΔE 0.063
Use #284583 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.