#284DAB
Closest named color: Cobalt (#1E488F). oklch(45.1% 0.157 264.6), rgb(40, 77, 171).
Aa
White text reads best on this color (7.66:1).
About this color
#284DAB is a medium-dark, vivid blue. In OKLCH its lightness is 45%, its chroma 0.157 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.049 away. White text reads best on it, at 7.66:1.
| Hue family | Blues |
| Lightness | medium-dark (45%) |
| Chroma | vivid (0.157) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.73:1 |
| White text | 7.66:1 |
Values
| HEX | #284DAB |
| RGB | rgb(40, 77, 171) |
| HSL | hsl(223, 62%, 41%) |
| OKLCH | oklch(45.1% 0.157 264.6) |
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 #284DAB | 7.66:1 | AAA | Lc -91.0 | Preferred for body text |
| Black text on #284DAB | 2.73:1 | Fails | Lc 17.9 | Dividers and decoration only |
| #284DAB text on white | 7.66:1 | AAA | Lc 86.2 | Fine for body text |
| #284DAB text on black | 2.73:1 | Fails | Lc -15.9 | 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
#C9D9FC
oklch(88.5% 0.051 265.9)
-
Step 300
300
#A3C0FD
oklch(80.9% 0.092 264.7)
-
Step 400
400
#729DFC
oklch(70.7% 0.147 264.5)
-
Step 500
500
#4F81F9
oklch(63.1% 0.187 264.6)
-
Step 600
600
#3567E8
oklch(55.6% 0.203 264.6)
-
Step 700
700
#2854CA
oklch(49% 0.19 264.6)
-
Step 800
800 (this color)
#284DAB
oklch(45.1% 0.157 264.6)
-
Step 900
900
#203C81
oklch(37.7% 0.121 264.6)
-
Step 950
950
#13244C
oklch(27.1% 0.077 264.5)
#284DAB 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) | #005AAE | 0.035 |
| Deuteranopia (no green cones) | #004DA9 | 0.022 |
| Tritanopia (no blue cones) | #006474 | 0.124 |
| Achromatopsia (no color) | #535353 | 0.157 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #284DAB
#284DAB
oklch(45.1% 0.157 264.6)
- #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 #284DAB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.049
- Blue Blue #2242C7 ΔE 0.052
- Sapphire #2138AB ΔE 0.052
- Blueberry #464196 ΔE 0.053
- Dusk Blue #26538D ΔE 0.054
- Denim Blue #3B5B92 ΔE 0.064
- Light Navy #155084 ΔE 0.068
- Majorelle Blue #3F37C9 ΔE 0.069
Use #284DAB 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.