#2A3783
Closest named color: Twilight Blue (#0A437A). oklch(37.3% 0.128 271.5), rgb(42, 55, 131).
Aa
White text reads best on this color (10.64:1).
About this color
#2A3783 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.128 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.044 away. White text reads best on it, at 10.64:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.128) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.97:1 |
| White text | 10.64:1 |
Values
| HEX | #2A3783 |
| RGB | rgb(42, 55, 131) |
| HSL | hsl(231, 51%, 34%) |
| OKLCH | oklch(37.3% 0.128 271.5) |
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 #2A3783 | 10.64:1 | AAA | Lc -98.3 | Preferred for body text |
| Black text on #2A3783 | 1.97:1 | Fails | Lc 9.6 | Not readable |
| #2A3783 text on white | 10.64:1 | AAA | Lc 94.3 | Preferred for body text |
| #2A3783 text on black | 1.97:1 | Fails | Lc -8.3 | 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
#E3E9FD
oklch(93.5% 0.028 272.5)
-
Step 200
200
#CCD8FD
oklch(88.5% 0.053 271.1)
-
Step 300
300
#AABDFF
oklch(80.8% 0.096 271.7)
-
Step 400
400
#7F98FF
oklch(70.6% 0.153 271.7)
-
Step 500
500
#617BFE
oklch(63.2% 0.196 271.3)
-
Step 600
600
#4B5FED
oklch(55.5% 0.213 271.4)
-
Step 700
700
#3D4DCF
oklch(49.1% 0.199 271.4)
-
Step 800
800
#3240A7
oklch(42.6% 0.165 271.5)
-
Step 900
900 (this color)
#2A3783
oklch(37.3% 0.128 271.5)
-
Step 950
950
#19224D
oklch(27.1% 0.08 271.2)
#2A3783 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) | #004286 | 0.038 |
| Deuteranopia (no green cones) | #003A81 | 0.033 |
| Tritanopia (no blue cones) | #004957 | 0.106 |
| Achromatopsia (no color) | #3E3E3E | 0.128 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2A3783
#2A3783
oklch(37.3% 0.128 271.5)
- #4F3E00
#4F3E00
oklch(37.1% 0.076 91.2)
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 #2A3783, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.044
- Cobalt #1E488F ΔE 0.048
- Dark Slate Blue #483D8B ΔE 0.052
- Marine Blue #01386A ΔE 0.057
- Blueberry #464196 ΔE 0.060
- Sapphire #2138AB ΔE 0.066
- Light Navy #155084 ΔE 0.070
- Dusk Blue #26538D ΔE 0.078
Use #2A3783 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.