#2A23A8
Closest named color: Indigo Blue (#3A18B1). oklch(37.7% 0.2 273.4), rgb(42, 35, 168).
Aa
White text reads best on this color (11.02:1).
About this color
#2A23A8 is a dark, vivid blue. In OKLCH its lightness is 38%, its chroma 0.200 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Indigo Blue (#3A18B1), ΔE 0.029 away. White text reads best on it, at 11.02:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | vivid (0.200) |
| Temperature | cool |
| Nearest name | Indigo Blue (#3A18B1) |
| Black text | 1.90:1 |
| White text | 11.02:1 |
Values
| HEX | #2A23A8 |
| RGB | rgb(42, 35, 168) |
| HSL | hsl(243, 66%, 40%) |
| OKLCH | oklch(37.7% 0.2 273.4) |
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 #2A23A8 | 11.02:1 | AAA | Lc -98.3 | Preferred for body text |
| Black text on #2A23A8 | 1.90:1 | Fails | Lc 9.6 | Not readable |
| #2A23A8 text on white | 11.02:1 | AAA | Lc 94.3 | Preferred for body text |
| #2A23A8 text on black | 1.90:1 | Fails | Lc -8.2 | 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 900.
-
Step 50
50
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E3E9FF
oklch(93.6% 0.03 273.6)
-
Step 200
200
#CDD7FF
oklch(88.4% 0.056 274.2)
-
Step 300
300
#ACBDFF
oklch(80.9% 0.095 273)
-
Step 400
400
#8397FF
oklch(70.7% 0.153 273.6)
-
Step 500
500
#6679FF
oklch(63.1% 0.198 273.3)
-
Step 600
600
#4F55FF
oklch(55.7% 0.246 273.5)
-
Step 700
700
#4124FF
oklch(49.1% 0.289 273.5)
-
Step 800
800
#3418D7
oklch(42.7% 0.257 273.3)
-
Step 900
900 (this color)
#2A23A8
oklch(37.7% 0.2 273.4)
-
Step 950
950
#171862
oklch(26.9% 0.126 273.4)
#2A23A8 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) | #0042AC | 0.063 |
| Deuteranopia (no green cones) | #0036A6 | 0.042 |
| Tritanopia (no blue cones) | #004C65 | 0.156 |
| Achromatopsia (no color) | #3C3C3C | 0.201 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2A23A8
#2A23A8
oklch(37.7% 0.2 273.4)
- #4F4000
#4F4000
oklch(37.6% 0.077 93.9)
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 #2A23A8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Indigo Blue #3A18B1 ΔE 0.029
- Sapphire #2138AB ΔE 0.039
- Ultramarine #2000B1 ΔE 0.040
- Imperial Purple #480CA8 ΔE 0.055
- Cobalt Blue #030AA7 ΔE 0.057
- Royal #0C1793 ΔE 0.059
- True Blue #010FCC ΔE 0.071
- Medium Blue #0000CD ΔE 0.076
Use #2A23A8 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.