#3F42A7
Closest named color: Blueberry (#464196). oklch(43.8% 0.159 276.3), rgb(63, 66, 167).
Aa
White text reads best on this color (8.23:1).
About this color
#3F42A7 is a dark, vivid blue. In OKLCH its lightness is 44%, its chroma 0.159 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.029 away. White text reads best on it, at 8.23:1.
| Hue family | Blues |
| Lightness | dark (44%) |
| Chroma | vivid (0.159) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.54:1 |
| White text | 8.23:1 |
Values
| HEX | #3F42A7 |
| RGB | rgb(63, 66, 167) |
| HSL | hsl(238, 45%, 45%) |
| OKLCH | oklch(43.8% 0.159 276.3) |
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 #3F42A7 | 8.23:1 | AAA | Lc -92.7 | Preferred for body text |
| Black text on #3F42A7 | 2.54:1 | Fails | Lc 15.9 | Dividers and decoration only |
| #3F42A7 text on white | 8.23:1 | AAA | Lc 88.1 | Fine for body text |
| #3F42A7 text on black | 2.54:1 | Fails | Lc -14.1 | 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
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E5E9FC
oklch(93.7% 0.026 276.4)
-
Step 200
200
#CFD7FC
oklch(88.5% 0.052 275.7)
-
Step 300
300
#B0BCFD
oklch(80.9% 0.093 276)
-
Step 400
400
#8996FC
oklch(70.7% 0.149 276.4)
-
Step 500
500
#6F78F9
oklch(63.1% 0.189 276.5)
-
Step 600
600
#595DE8
oklch(55.6% 0.206 276.2)
-
Step 700
700
#4A4BCA
oklch(49.1% 0.192 276.4)
-
Step 800
800 (this color)
#3F42A7
oklch(43.8% 0.159 276.3)
-
Step 900
900
#333781
oklch(37.8% 0.123 276.5)
-
Step 950
950
#1D214C
oklch(27.1% 0.078 275.8)
#3F42A7 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) | #0053AA | 0.057 |
| Deuteranopia (no green cones) | #004AA5 | 0.051 |
| Tritanopia (no blue cones) | #005B6E | 0.135 |
| Achromatopsia (no color) | #4F4F4F | 0.159 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F42A7
#3F42A7
oklch(43.8% 0.159 276.3)
- #615100
#615100
oklch(43.8% 0.09 95.9)
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 #3F42A7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.029
- Sapphire #2138AB ΔE 0.048
- Dark Slate Blue #483D8B ΔE 0.048
- Cobalt #1E488F ΔE 0.057
- Majorelle Blue #3F37C9 ΔE 0.058
- Blue With A Hint Of Purple #533CC6 ΔE 0.058
- Blue Blue #2242C7 ΔE 0.060
- Blurple #5539CC ΔE 0.068
Use #3F42A7 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.