#28428B
Closest named color: Cobalt (#1E488F). oklch(40.2% 0.126 266.1), rgb(40, 66, 139).
Aa
White text reads best on this color (9.36:1).
About this color
#28428B is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.126 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.018 away. White text reads best on it, at 9.36:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.24:1 |
| White text | 9.36:1 |
Values
| HEX | #28428B |
| RGB | rgb(40, 66, 139) |
| HSL | hsl(224, 55%, 35%) |
| OKLCH | oklch(40.2% 0.126 266.1) |
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 #28428B | 9.36:1 | AAA | Lc -95.6 | Preferred for body text |
| Black text on #28428B | 2.24:1 | Fails | Lc 12.7 | Not readable |
| #28428B text on white | 9.36:1 | AAA | Lc 91.3 | Preferred for body text |
| #28428B text on black | 2.24:1 | Fails | Lc -11.1 | 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
#F1F5FE
oklch(97% 0.013 266.7)
-
Step 100
100
#E1EAFD
oklch(93.6% 0.028 265.4)
-
Step 200
200
#C9D9FD
oklch(88.5% 0.053 266.4)
-
Step 300
300
#A4C0FE
oklch(81% 0.093 265.6)
-
Step 400
400
#749CFE
oklch(70.7% 0.15 265.9)
-
Step 500
500
#527FFC
oklch(63% 0.193 266.1)
-
Step 600
600
#3964EB
oklch(55.5% 0.209 266.1)
-
Step 700
700
#2D52CD
oklch(49.1% 0.195 266.3)
-
Step 800
800
#2544A6
oklch(42.7% 0.162 266.1)
-
Step 900
900 (this color)
#28428B
oklch(40.2% 0.126 266.1)
-
Step 950
950
#14234D
oklch(27% 0.08 266.3)
#28428B 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) | #154B8E | 0.027 |
| Deuteranopia (no green cones) | #00428A | 0.027 |
| Tritanopia (no blue cones) | #005360 | 0.101 |
| Achromatopsia (no color) | #464646 | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #28428B
#28428B
oklch(40.2% 0.126 266.1)
- #5C4400
#5C4400
oklch(40.2% 0.082 85.6)
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 #28428B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.018
- Twilight Blue #0A437A ΔE 0.038
- Light Navy #155084 ΔE 0.044
- Dark Slate Blue #483D8B ΔE 0.045
- Blueberry #464196 ΔE 0.045
- Dusk Blue #26538D ΔE 0.048
- Deep Sea Blue #015482 ΔE 0.058
- Sapphire #2138AB ΔE 0.059
Use #28428B 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.