#3663DF
Closest named color: Royal Blue (#4169E1). oklch(54.2% 0.196 265.2), rgb(54, 99, 223).
Aa
White text reads best on this color (5.24:1).
About this color
#3663DF is a medium-dark, vivid blue. In OKLCH its lightness is 54%, its chroma 0.196 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.020 away. White text reads best on it, at 5.24:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | vivid (0.196) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.00:1 |
| White text | 5.24:1 |
Values
| HEX | #3663DF |
| RGB | rgb(54, 99, 223) |
| HSL | hsl(224, 73%, 54%) |
| OKLCH | oklch(54.2% 0.196 265.2) |
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 #3663DF | 5.24:1 | AA | Lc -80.8 | Fine for body text |
| Black text on #3663DF | 4.00:1 | AA large text | Lc 28.6 | Dividers and decoration only |
| #3663DF text on white | 5.24:1 | AA | Lc 75.5 | Fine for body text |
| #3663DF text on black | 4.00:1 | AA large text | Lc -26.3 | Dividers and decoration only |
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 600.
-
Step 50
50
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E2EAFC
oklch(93.6% 0.026 266.6)
-
Step 200
200
#CAD9FA
oklch(88.5% 0.048 266)
-
Step 300
300
#A5C0FA
oklch(80.9% 0.088 265.1)
-
Step 400
400
#759DF8
oklch(70.6% 0.141 265)
-
Step 500
500
#5381F5
oklch(63% 0.181 265.3)
-
Step 600
600 (this color)
#3663DF
oklch(54.2% 0.196 265.2)
-
Step 700
700
#2D55C6
oklch(49.1% 0.182 265.3)
-
Step 800
800
#2546A0
oklch(42.6% 0.151 265.2)
-
Step 900
900
#223C7F
oklch(37.6% 0.118 265.2)
-
Step 950
950
#14244A
oklch(27% 0.074 264.7)
#3663DF 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) | #0074E3 | 0.043 |
| Deuteranopia (no green cones) | #0065DD | 0.026 |
| Tritanopia (no blue cones) | #008297 | 0.155 |
| Achromatopsia (no color) | #6C6C6C | 0.196 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3663DF
#3663DF
oklch(54.2% 0.196 265.2)
- #8C6900
#8C6900
oklch(54.1% 0.111 85.5)
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 #3663DF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.020
- Neon Blue #4361EE ΔE 0.027
- Azul #1D5DEC ΔE 0.031
- Warm Blue #4B57DB ΔE 0.032
- Cerulean Blue #056EEE ΔE 0.037
- Bright Blue #0165FC ΔE 0.049
- Dark Periwinkle #665FD1 ΔE 0.060
- Iris #6258C4 ΔE 0.067
Use #3663DF 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.