#3F63E3
Closest named color: Royal Blue (#4169E1). oklch(54.9% 0.199 267.4), rgb(63, 99, 227).
Aa
White text reads best on this color (5.11:1).
About this color
#3F63E3 is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.199 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.016 away. White text reads best on it, at 5.11:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.199) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.10:1 |
| White text | 5.11:1 |
Values
| HEX | #3F63E3 |
| RGB | rgb(63, 99, 227) |
| HSL | hsl(227, 75%, 57%) |
| OKLCH | oklch(54.9% 0.199 267.4) |
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 #3F63E3 | 5.11:1 | AA | Lc -80.2 | Fine for body text |
| Black text on #3F63E3 | 4.10:1 | AA large text | Lc 29.3 | Dividers and decoration only |
| #3F63E3 text on white | 5.11:1 | AA | Lc 74.8 | Content text, not long reading |
| #3F63E3 text on black | 4.10:1 | AA large text | Lc -27.0 | 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
#CBD9FB
oklch(88.6% 0.049 267.7)
-
Step 300
300
#A7BFFB
oklch(80.8% 0.089 267.5)
-
Step 400
400
#799CFA
oklch(70.8% 0.143 267.3)
-
Step 500
500
#5980F7
oklch(63.2% 0.183 267.4)
-
Step 600
600 (this color)
#3F63E3
oklch(54.9% 0.199 267.4)
-
Step 700
700
#3353C7
oklch(49% 0.184 267.3)
-
Step 800
800
#2B45A1
oklch(42.7% 0.152 267.5)
-
Step 900
900
#263B80
oklch(37.7% 0.119 267.6)
-
Step 950
950
#16234B
oklch(26.9% 0.076 267.6)
#3F63E3 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) | #0076E7 | 0.050 |
| Deuteranopia (no green cones) | #0067E0 | 0.034 |
| Tritanopia (no blue cones) | #008399 | 0.160 |
| Achromatopsia (no color) | #6E6E6E | 0.199 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F63E3
#3F63E3
oklch(54.9% 0.199 267.4)
- #8D6C00
#8D6C00
oklch(54.9% 0.112 87.4)
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 #3F63E3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.016
- Neon Blue #4361EE ΔE 0.018
- Warm Blue #4B57DB ΔE 0.030
- Azul #1D5DEC ΔE 0.035
- Cerulean Blue #056EEE ΔE 0.038
- Bright Blue #0165FC ΔE 0.048
- Dark Periwinkle #665FD1 ΔE 0.055
- Slate Blue #6A5ACD ΔE 0.064
Use #3F63E3 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.