#3F63DF
Closest named color: Royal Blue (#4169E1). oklch(54.6% 0.193 267.3), rgb(63, 99, 223).
Aa
White text reads best on this color (5.17:1).
About this color
#3F63DF is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.193 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.015 away. White text reads best on it, at 5.17:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.193) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.06:1 |
| White text | 5.17:1 |
Values
| HEX | #3F63DF |
| RGB | rgb(63, 99, 223) |
| HSL | hsl(227, 71%, 56%) |
| OKLCH | oklch(54.6% 0.193 267.3) |
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 #3F63DF | 5.17:1 | AA | Lc -80.5 | Fine for body text |
| Black text on #3F63DF | 4.06:1 | AA large text | Lc 29.0 | Dividers and decoration only |
| #3F63DF text on white | 5.17:1 | AA | Lc 75.1 | Fine for body text |
| #3F63DF text on black | 4.06:1 | AA large text | Lc -26.6 | 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
#E2EAFB
oklch(93.6% 0.025 265.6)
-
Step 200
200
#CBD9FA
oklch(88.5% 0.048 267.2)
-
Step 300
300
#A8BFFA
oklch(80.9% 0.088 267.9)
-
Step 400
400
#7A9CF7
oklch(70.7% 0.139 267.3)
-
Step 500
500
#5A80F4
oklch(63.1% 0.178 267.5)
-
Step 600
600 (this color)
#3F63DF
oklch(54.6% 0.193 267.3)
-
Step 700
700
#3454C5
oklch(49.1% 0.18 267.3)
-
Step 800
800
#2B469F
oklch(42.8% 0.148 267.1)
-
Step 900
900
#263C7E
oklch(37.7% 0.115 266.9)
-
Step 950
950
#16234A
oklch(26.9% 0.074 267.4)
#3F63DF 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) | #0075E3 | 0.048 |
| Deuteranopia (no green cones) | #0066DD | 0.034 |
| Tritanopia (no blue cones) | #008197 | 0.154 |
| Achromatopsia (no color) | #6D6D6D | 0.194 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F63DF
#3F63DF
oklch(54.6% 0.193 267.3)
- #8C6B00
#8C6B00
oklch(54.6% 0.112 87.2)
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 #3F63DF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.015
- Neon Blue #4361EE ΔE 0.024
- Warm Blue #4B57DB ΔE 0.029
- Azul #1D5DEC ΔE 0.037
- Cerulean Blue #056EEE ΔE 0.041
- Dark Periwinkle #665FD1 ΔE 0.052
- Bright Blue #0165FC ΔE 0.053
- Iris #6258C4 ΔE 0.061
Use #3F63DF 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.