#15428B
Closest named color: Cobalt (#1E488F). oklch(39.4% 0.131 259.9), rgb(21, 66, 139).
Aa
White text reads best on this color (9.61:1).
About this color
#15428B is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.131 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.020 away. White text reads best on it, at 9.61:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.18:1 |
| White text | 9.61:1 |
Values
| HEX | #15428B |
| RGB | rgb(21, 66, 139) |
| HSL | hsl(217, 74%, 31%) |
| OKLCH | oklch(39.4% 0.131 259.9) |
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 #15428B | 9.61:1 | AAA | Lc -96.1 | Preferred for body text |
| Black text on #15428B | 2.18:1 | Fails | Lc 12.2 | Not readable |
| #15428B text on white | 9.61:1 | AAA | Lc 91.8 | Preferred for body text |
| #15428B text on black | 2.18:1 | Fails | Lc -10.6 | 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
#F0F6FF
oklch(97.1% 0.014 258.3)
-
Step 100
100
#DFEBFD
oklch(93.6% 0.028 258.4)
-
Step 200
200
#C4DAFE
oklch(88.4% 0.055 260.3)
-
Step 300
300
#9CC2FF
oklch(80.9% 0.096 259.7)
-
Step 400
400
#659FFF
oklch(70.6% 0.154 260)
-
Step 500
500
#3883FF
oklch(63% 0.199 260)
-
Step 600
600
#0B68F0
oklch(55.6% 0.219 260)
-
Step 700
700
#0056CF
oklch(49.1% 0.2 260)
-
Step 800
800
#0447A9
oklch(42.7% 0.169 259.9)
-
Step 900
900 (this color)
#15428B
oklch(39.4% 0.131 259.9)
-
Step 950
950
#0B244E
oklch(26.9% 0.084 260.2)
#15428B 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) | #114A8E | 0.022 |
| Deuteranopia (no green cones) | #00408A | 0.013 |
| Tritanopia (no blue cones) | #005460 | 0.101 |
| Achromatopsia (no color) | #454545 | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #15428B
#15428B
oklch(39.4% 0.131 259.9)
- #5D4000
#5D4000
oklch(39.4% 0.082 79.6)
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 #15428B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.020
- Twilight Blue #0A437A ΔE 0.030
- Light Navy #155084 ΔE 0.044
- Dusk Blue #26538D ΔE 0.053
- Deep Sea Blue #015482 ΔE 0.057
- Sapphire #2138AB ΔE 0.059
- Blueberry #464196 ΔE 0.061
- Dark Slate Blue #483D8B ΔE 0.062
Use #15428B 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.