#3F6DDD
Closest named color: Royal Blue (#4169E1). oklch(56.4% 0.179 264.5), rgb(63, 109, 221).
Aa
White text reads best on this color (4.72:1).
About this color
#3F6DDD is a medium-dark, vivid blue. In OKLCH its lightness is 56%, its chroma 0.179 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.012 away. White text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.179) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.44:1 |
| White text | 4.72:1 |
Values
| HEX | #3F6DDD |
| RGB | rgb(63, 109, 221) |
| HSL | hsl(223, 70%, 56%) |
| OKLCH | oklch(56.4% 0.179 264.5) |
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 #3F6DDD | 4.72:1 | AA | Lc -77.8 | Fine for body text |
| Black text on #3F6DDD | 4.44:1 | AA large text | Lc 31.7 | Non-text elements, placeholder text |
| #3F6DDD text on white | 4.72:1 | AA | Lc 72.4 | Content text, not long reading |
| #3F6DDD text on black | 4.44:1 | AA large text | Lc -29.3 | 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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFA
oklch(93.6% 0.023 264.5)
-
Step 200
200
#CBD9F8
oklch(88.5% 0.045 266.2)
-
Step 300
300
#A7C1F5
oklch(81% 0.079 264)
-
Step 400
400
#789EF1
oklch(70.6% 0.129 264.6)
-
Step 500
500
#5684EC
oklch(63.2% 0.164 264.3)
-
Step 600
600 (this color)
#3F6DDD
oklch(56.4% 0.179 264.5)
-
Step 700
700
#2F58BD
oklch(49.1% 0.166 264.4)
-
Step 800
800
#284999
oklch(42.8% 0.137 264.5)
-
Step 900
900
#243E7A
oklch(37.8% 0.107 264.3)
-
Step 950
950
#152547
oklch(27.1% 0.067 263.6)
#3F6DDD 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) | #277BE1 | 0.036 |
| Deuteranopia (no green cones) | #006CDB | 0.033 |
| Tritanopia (no blue cones) | #00889B | 0.143 |
| Achromatopsia (no color) | #737373 | 0.179 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F6DDD
#3F6DDD
oklch(56.4% 0.179 264.5)
- #956F00
#956F00
oklch(56.4% 0.116 84.7)
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 #3F6DDD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.012
- Cerulean Blue #056EEE ΔE 0.038
- Neon Blue #4361EE ΔE 0.039
- Warm Blue #4B57DB ΔE 0.052
- Dark Periwinkle #665FD1 ΔE 0.055
- Azul #1D5DEC ΔE 0.056
- Clear Blue #247AFD ΔE 0.056
- Windows Blue #3778BF ΔE 0.059
Use #3F6DDD 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.