#3366DD
Closest named color: Royal Blue (#4169E1). oklch(54.5% 0.19 263.7), rgb(51, 102, 221).
Aa
White text reads best on this color (5.14:1).
About this color
#3366DD is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.190 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.017 away. White text reads best on it, at 5.14:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.190) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.08:1 |
| White text | 5.14:1 |
Values
| HEX | #3366DD |
| RGB | rgb(51, 102, 221) |
| HSL | hsl(222, 71%, 53%) |
| OKLCH | oklch(54.5% 0.19 263.7) |
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 #3366DD | 5.14:1 | AA | Lc -80.3 | Fine for body text |
| Black text on #3366DD | 4.08:1 | AA large text | Lc 29.2 | Dividers and decoration only |
| #3366DD text on white | 5.14:1 | AA | Lc 74.9 | Content text, not long reading |
| #3366DD text on black | 4.08:1 | AA large text | Lc -26.8 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E1EAFB
oklch(93.5% 0.025 263.3)
-
Step 200
200
#C9DAFA
oklch(88.6% 0.048 263.1)
-
Step 300
300
#A4C1F9
oklch(81% 0.086 263.3)
-
Step 400
400
#749EF6
oklch(70.7% 0.137 263.9)
-
Step 500
500
#5183F2
oklch(63.1% 0.175 263.9)
-
Step 600
600 (this color)
#3366DD
oklch(54.5% 0.19 263.7)
-
Step 700
700
#2957C3
oklch(49.1% 0.177 263.7)
-
Step 800
800
#23489E
oklch(42.8% 0.147 263.8)
-
Step 900
900
#213D7D
oklch(37.6% 0.114 264)
-
Step 950
950
#132449
oklch(26.8% 0.072 263.7)
#3366DD 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) | #0076E1 | 0.041 |
| Deuteranopia (no green cones) | #0066DB | 0.024 |
| Tritanopia (no blue cones) | #008398 | 0.148 |
| Achromatopsia (no color) | #6D6D6D | 0.191 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3366DD
#3366DD
oklch(54.5% 0.19 263.7)
- #8F6900
#8F6900
oklch(54.5% 0.112 83.5)
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 #3366DD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.017
- Neon Blue #4361EE ΔE 0.032
- Cerulean Blue #056EEE ΔE 0.034
- Azul #1D5DEC ΔE 0.036
- Warm Blue #4B57DB ΔE 0.039
- Bright Blue #0165FC ΔE 0.051
- Dark Periwinkle #665FD1 ΔE 0.061
- Clear Blue #247AFD ΔE 0.066
Use #3366DD 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.