#2A3289
Closest named color: Cobalt (#1E488F). oklch(36.8% 0.143 273.1), rgb(42, 50, 137).
Aa
White text reads best on this color (10.96:1).
About this color
#2A3289 is a dark, vivid blue. In OKLCH its lightness is 37%, its chroma 0.143 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.057 away. White text reads best on it, at 10.96:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | vivid (0.143) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 1.91:1 |
| White text | 10.96:1 |
Values
| HEX | #2A3289 |
| RGB | rgb(42, 50, 137) |
| HSL | hsl(235, 53%, 35%) |
| OKLCH | oklch(36.8% 0.143 273.1) |
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 #2A3289 | 10.96:1 | AAA | Lc -98.8 | Preferred for body text |
| Black text on #2A3289 | 1.91:1 | Fails | Lc 9.0 | Not readable |
| #2A3289 text on white | 10.96:1 | AAA | Lc 94.9 | Preferred for body text |
| #2A3289 text on black | 1.91:1 | Fails | Lc -7.7 | 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
#8297FF
oklch(70.6% 0.154 273.2)
-
Step 500
500
#6579FF
oklch(63.1% 0.198 273)
-
Step 600
600
#4E57FB
oklch(55.6% 0.239 273.2)
-
Step 700
700
#4045DB
oklch(49% 0.222 273.2)
-
Step 800
800
#343BB1
oklch(42.8% 0.184 273)
-
Step 900
900 (this color)
#2A3289
oklch(36.8% 0.143 273.1)
-
Step 950
950
#192052
oklch(27% 0.091 272.8)
#2A3289 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) | #00418C | 0.044 |
| Deuteranopia (no green cones) | #003887 | 0.035 |
| Tritanopia (no blue cones) | #004858 | 0.117 |
| Achromatopsia (no color) | #3C3C3C | 0.144 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2A3289
#2A3289
oklch(36.8% 0.143 273.1)
- #4D3E00
#4D3E00
oklch(36.9% 0.076 93.4)
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 #2A3289, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.057
- Twilight Blue #0A437A ΔE 0.057
- Dark Slate Blue #483D8B ΔE 0.058
- Sapphire #2138AB ΔE 0.058
- Blueberry #464196 ΔE 0.064
- Marine Blue #01386A ΔE 0.067
- Royal #0C1793 ΔE 0.070
- Indigo Blue #3A18B1 ΔE 0.076
Use #2A3289 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.