#284DA9
Closest named color: Cobalt (#1E488F). oklch(44.9% 0.154 264.4), rgb(40, 77, 169).
Aa
White text reads best on this color (7.70:1).
About this color
#284DA9 is a dark, vivid blue. In OKLCH its lightness is 45%, its chroma 0.154 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.046 away. White text reads best on it, at 7.70:1.
| Hue family | Blues |
| Lightness | dark (45%) |
| Chroma | vivid (0.154) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.72:1 |
| White text | 7.70:1 |
Values
| HEX | #284DA9 |
| RGB | rgb(40, 77, 169) |
| HSL | hsl(223, 62%, 41%) |
| OKLCH | oklch(44.9% 0.154 264.4) |
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 #284DA9 | 7.70:1 | AAA | Lc -91.1 | Preferred for body text |
| Black text on #284DA9 | 2.72:1 | Fails | Lc 17.7 | Dividers and decoration only |
| #284DA9 text on white | 7.70:1 | AAA | Lc 86.3 | Fine for body text |
| #284DA9 text on black | 2.72:1 | Fails | Lc -15.8 | Dividers and decoration only |
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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E1EAFC
oklch(93.6% 0.026 264.4)
-
Step 200
200
#C9D9FB
oklch(88.4% 0.05 265.4)
-
Step 300
300
#A4C0FC
oklch(80.9% 0.091 265)
-
Step 400
400
#739DFA
oklch(70.6% 0.144 264.6)
-
Step 500
500
#5082F7
oklch(63.2% 0.183 264.4)
-
Step 600
600
#3567E6
oklch(55.5% 0.2 264.5)
-
Step 700
700
#2955C8
oklch(49.1% 0.186 264.5)
-
Step 800
800 (this color)
#284DA9
oklch(44.9% 0.154 264.4)
-
Step 900
900
#203C80
oklch(37.6% 0.12 264.5)
-
Step 950
950
#13244B
oklch(27% 0.076 264.2)
#284DA9 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) | #0059AC | 0.033 |
| Deuteranopia (no green cones) | #004DA7 | 0.022 |
| Tritanopia (no blue cones) | #006373 | 0.121 |
| Achromatopsia (no color) | #535353 | 0.154 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #284DA9
#284DA9
oklch(44.9% 0.154 264.4)
- #6D5000
#6D5000
oklch(45% 0.092 84.4)
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 #284DA9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.046
- Dusk Blue #26538D ΔE 0.051
- Blueberry #464196 ΔE 0.052
- Sapphire #2138AB ΔE 0.053
- Blue Blue #2242C7 ΔE 0.055
- Denim Blue #3B5B92 ΔE 0.062
- Light Navy #155084 ΔE 0.065
- Dark Slate Blue #483D8B ΔE 0.069
Use #284DA9 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.