#2A3B81
Closest named color: Twilight Blue (#0A437A). oklch(38% 0.12 269.6), rgb(42, 59, 129).
Aa
White text reads best on this color (10.28:1).
About this color
#2A3B81 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.120 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.035 away. White text reads best on it, at 10.28:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.120) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.04:1 |
| White text | 10.28:1 |
Values
| HEX | #2A3B81 |
| RGB | rgb(42, 59, 129) |
| HSL | hsl(228, 51%, 34%) |
| OKLCH | oklch(38% 0.12 269.6) |
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 #2A3B81 | 10.28:1 | AAA | Lc -97.6 | Preferred for body text |
| Black text on #2A3B81 | 2.04:1 | Fails | Lc 10.4 | Not readable |
| #2A3B81 text on white | 10.28:1 | AAA | Lc 93.6 | Preferred for body text |
| #2A3B81 text on black | 2.04:1 | Fails | Lc -8.9 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3EAFC
oklch(93.7% 0.025 268.8)
-
Step 200
200
#CCD8FB
oklch(88.4% 0.05 270.4)
-
Step 300
300
#A9BEFB
oklch(80.8% 0.09 269.6)
-
Step 400
400
#7D9AFA
oklch(70.6% 0.144 269.7)
-
Step 500
500
#5F7EF7
oklch(63.1% 0.183 269.7)
-
Step 600
600
#4863E6
oklch(55.6% 0.2 269.8)
-
Step 700
700
#3A51C8
oklch(49.1% 0.186 269.8)
-
Step 800
800
#3043A1
oklch(42.6% 0.153 270)
-
Step 900
900 (this color)
#2A3B81
oklch(38% 0.12 269.6)
-
Step 950
950
#18234B
oklch(27.1% 0.075 269.3)
#2A3B81 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) | #0F4583 | 0.033 |
| Deuteranopia (no green cones) | #003D80 | 0.032 |
| Tritanopia (no blue cones) | #004B58 | 0.098 |
| Achromatopsia (no color) | #404040 | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2A3B81
#2A3B81
oklch(38% 0.12 269.6)
- #534000
#534000
oklch(38.1% 0.078 89.6)
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 #2A3B81, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.035
- Cobalt #1E488F ΔE 0.040
- Dark Slate Blue #483D8B ΔE 0.049
- Marine Blue #01386A ΔE 0.055
- Blueberry #464196 ΔE 0.057
- Light Navy #155084 ΔE 0.059
- Dusk Blue #26538D ΔE 0.068
- Sapphire #2138AB ΔE 0.070
Use #2A3B81 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.