#3731BE
Closest named color: Majorelle Blue (#3F37C9). oklch(42.7% 0.21 274.7), rgb(55, 49, 190).
Aa
White text reads best on this color (8.95:1).
About this color
#3731BE is a dark, vivid blue. In OKLCH its lightness is 43%, its chroma 0.210 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Majorelle Blue (#3F37C9), ΔE 0.026 away. White text reads best on it, at 8.95:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | vivid (0.210) |
| Temperature | cool |
| Nearest name | Majorelle Blue (#3F37C9) |
| Black text | 2.34:1 |
| White text | 8.95:1 |
Values
| HEX | #3731BE |
| RGB | rgb(55, 49, 190) |
| HSL | hsl(243, 59%, 47%) |
| OKLCH | oklch(42.7% 0.21 274.7) |
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 #3731BE | 8.95:1 | AAA | Lc -94.1 | Preferred for body text |
| Black text on #3731BE | 2.34:1 | Fails | Lc 14.4 | Not readable |
| #3731BE text on white | 8.95:1 | AAA | Lc 89.6 | Fine for body text |
| #3731BE text on black | 2.34:1 | Fails | Lc -12.7 | 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
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E3E9FF
oklch(93.6% 0.03 273.6)
-
Step 200
200
#CED7FF
oklch(88.5% 0.056 275.2)
-
Step 300
300
#AEBCFF
oklch(80.9% 0.096 274.9)
-
Step 400
400
#8596FF
oklch(70.6% 0.154 274.8)
-
Step 500
500
#6A78FF
oklch(63.2% 0.198 274.8)
-
Step 600
600
#5353FF
oklch(55.6% 0.247 274.8)
-
Step 700
700
#4438EB
oklch(49.1% 0.253 274.7)
-
Step 800
800 (this color)
#3731BE
oklch(42.7% 0.21 274.7)
-
Step 900
900
#2E2F96
oklch(37.8% 0.164 274.8)
-
Step 950
950
#1A1D58
oklch(27% 0.104 274.7)
#3731BE 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) | #0050C2 | 0.068 |
| Deuteranopia (no green cones) | #0043BB | 0.048 |
| Tritanopia (no blue cones) | #005A75 | 0.166 |
| Achromatopsia (no color) | #494949 | 0.211 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3731BE
#3731BE
oklch(42.7% 0.21 274.7)
- #5E4E00
#5E4E00
oklch(42.8% 0.088 95.4)
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 #3731BE, closest first.
No curated palette has a color within ΔE 0.04 of #3731BE.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Majorelle Blue #3F37C9 ΔE 0.026
- Blue Blue #2242C7 ΔE 0.039
- Sapphire #2138AB ΔE 0.040
- Indigo Blue #3A18B1 ΔE 0.044
- Blue With A Hint Of Purple #533CC6 ΔE 0.054
- Violet Blue #510AC9 ΔE 0.055
- Blurple #5539CC ΔE 0.057
- Imperial Purple #480CA8 ΔE 0.067
Use #3731BE 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.