#284D9C
Closest named color: Cobalt (#1E488F). oklch(43.9% 0.136 263.1), rgb(40, 77, 156).
Aa
White text reads best on this color (7.97:1).
About this color
#284D9C is a dark, moderately saturated blue. In OKLCH its lightness is 44%, its chroma 0.136 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.027 away. White text reads best on it, at 7.97:1.
| Hue family | Blues |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.136) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.63:1 |
| White text | 7.97:1 |
Values
| HEX | #284D9C |
| RGB | rgb(40, 77, 156) |
| HSL | hsl(221, 59%, 38%) |
| OKLCH | oklch(43.9% 0.136 263.1) |
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 #284D9C | 7.97:1 | AAA | Lc -92.0 | Preferred for body text |
| Black text on #284D9C | 2.63:1 | Fails | Lc 16.7 | Dividers and decoration only |
| #284D9C text on white | 7.97:1 | AAA | Lc 87.3 | Fine for body text |
| #284D9C text on black | 2.63:1 | Fails | Lc -14.8 | 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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFA
oklch(93.6% 0.023 264.5)
-
Step 200
200
#CADAF7
oklch(88.5% 0.044 262.4)
-
Step 300
300
#A6C1F5
oklch(80.9% 0.08 263.3)
-
Step 400
400
#769FF0
oklch(70.7% 0.128 263.1)
-
Step 500
500
#5385EB
oklch(63.2% 0.163 262.9)
-
Step 600
600
#396CD9
oklch(55.7% 0.176 263.1)
-
Step 700
700
#2C59BC
oklch(49.1% 0.164 263.3)
-
Step 800
800 (this color)
#284D9C
oklch(43.9% 0.136 263.1)
-
Step 900
900
#223E79
oklch(37.6% 0.106 263.2)
-
Step 950
950
#142547
oklch(27% 0.067 262.7)
#284D9C 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) | #1E569F | 0.024 |
| Deuteranopia (no green cones) | #004C9A | 0.024 |
| Tritanopia (no blue cones) | #00606D | 0.108 |
| Achromatopsia (no color) | #515151 | 0.136 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #284D9C
#284D9C
oklch(43.9% 0.136 263.1)
- #6A4D00
#6A4D00
oklch(44% 0.09 83.6)
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 #284D9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.027
- Dusk Blue #26538D ΔE 0.032
- Light Navy #155084 ΔE 0.045
- Blueberry #464196 ΔE 0.045
- Denim Blue #3B5B92 ΔE 0.052
- Light Navy Blue #2E5A88 ΔE 0.055
- Deep Sea Blue #015482 ΔE 0.055
- Twilight #4E518B ΔE 0.057
Use #284D9C 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.