#3F37A3
Closest named color: Blueberry (#464196). oklch(41.6% 0.167 279.5), rgb(63, 55, 163).
Aa
White text reads best on this color (9.18:1).
About this color
#3F37A3 is a dark, vivid blue. In OKLCH its lightness is 42%, its chroma 0.167 and its hue 280°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.035 away. White text reads best on it, at 9.18:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | vivid (0.167) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.28:1 |
| White text | 9.18:1 |
Values
| HEX | #3F37A3 |
| RGB | rgb(63, 55, 163) |
| HSL | hsl(244, 50%, 43%) |
| OKLCH | oklch(41.6% 0.167 279.5) |
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 #3F37A3 | 9.18:1 | AAA | Lc -95.0 | Preferred for body text |
| Black text on #3F37A3 | 2.28:1 | Fails | Lc 13.4 | Not readable |
| #3F37A3 text on white | 9.18:1 | AAA | Lc 90.6 | Preferred for body text |
| #3F37A3 text on black | 2.28:1 | Fails | Lc -11.7 | 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 800.
-
Step 50
50
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E5E8FD
oklch(93.5% 0.029 279.4)
-
Step 200
200
#D1D6FD
oklch(88.5% 0.054 279.5)
-
Step 300
300
#B3BAFF
oklch(80.8% 0.098 279.5)
-
Step 400
400
#8E93FF
oklch(70.6% 0.156 279.6)
-
Step 500
500
#7574FE
oklch(63.2% 0.2 279.3)
-
Step 600
600
#6157ED
oklch(55.6% 0.217 279.6)
-
Step 700
700
#5146CE
oklch(49.1% 0.201 279.6)
-
Step 800
800 (this color)
#3F37A3
oklch(41.6% 0.167 279.5)
-
Step 900
900
#373484
oklch(37.7% 0.13 279.8)
-
Step 950
950
#201F4D
oklch(26.9% 0.083 280.3)
#3F37A3 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) | #004CA6 | 0.065 |
| Deuteranopia (no green cones) | #0044A1 | 0.058 |
| Tritanopia (no blue cones) | #005368 | 0.141 |
| Achromatopsia (no color) | #484848 | 0.168 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F37A3
#3F37A3
oklch(41.6% 0.167 279.5)
- #574C00
#574C00
oklch(41.5% 0.086 99.8)
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 #3F37A3, closest first.
No curated palette has a color within ΔE 0.04 of #3F37A3.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.035
- Sapphire #2138AB ΔE 0.041
- Dark Slate Blue #483D8B ΔE 0.046
- Indigo Blue #3A18B1 ΔE 0.055
- Majorelle Blue #3F37C9 ΔE 0.061
- Imperial Purple #480CA8 ΔE 0.061
- Cobalt #1E488F ΔE 0.064
- Blue With A Hint Of Purple #533CC6 ΔE 0.066
Use #3F37A3 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.