#284A8F
Closest named color: Cobalt (#1E488F). oklch(42.3% 0.121 262.6), rgb(40, 74, 143).
Aa
White text reads best on this color (8.51:1).
About this color
#284A8F is a dark, moderately saturated blue. In OKLCH its lightness is 42%, its chroma 0.121 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.012 away. White text reads best on it, at 8.51:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | moderately saturated (0.121) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.46:1 |
| White text | 8.51:1 |
Values
| HEX | #284A8F |
| RGB | rgb(40, 74, 143) |
| HSL | hsl(220, 56%, 36%) |
| OKLCH | oklch(42.3% 0.121 262.6) |
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 #284A8F | 8.51:1 | AAA | Lc -93.5 | Preferred for body text |
| Black text on #284A8F | 2.46:1 | Fails | Lc 15.0 | Dividers and decoration only |
| #284A8F text on white | 8.51:1 | AAA | Lc 89.0 | Fine for body text |
| #284A8F text on black | 2.46:1 | Fails | Lc -13.2 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CBDAF4
oklch(88.5% 0.039 261.5)
-
Step 300
300
#A8C1EF
oklch(80.8% 0.071 262.5)
-
Step 400
400
#7AA0E7
oklch(70.7% 0.113 262.3)
-
Step 500
500
#5986E0
oklch(63% 0.145 262.9)
-
Step 600
600
#3F6ECE
oklch(55.6% 0.157 262.7)
-
Step 700
700
#315CB2
oklch(49.2% 0.145 262.4)
-
Step 800
800 (this color)
#284A8F
oklch(42.3% 0.121 262.6)
-
Step 900
900
#253F73
oklch(37.6% 0.095 262.7)
-
Step 950
950
#162543
oklch(26.8% 0.06 262.9)
#284A8F 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) | #265292 | 0.022 |
| Deuteranopia (no green cones) | #0D488E | 0.022 |
| Tritanopia (no blue cones) | #005A65 | 0.097 |
| Achromatopsia (no color) | #4D4D4D | 0.121 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #284A8F
#284A8F
oklch(42.3% 0.121 262.6)
- #654800
#654800
oklch(42.2% 0.087 82.1)
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 #284A8F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.012
- Dusk Blue #26538D ΔE 0.026
- Light Navy #155084 ΔE 0.030
- Deep Sea Blue #015482 ΔE 0.043
- Blueberry #464196 ΔE 0.045
- Twilight Blue #0A437A ΔE 0.048
- Dark Slate Blue #483D8B ΔE 0.051
- Light Navy Blue #2E5A88 ΔE 0.052
Use #284A8F 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.