#3366E3
Closest named color: Royal Blue (#4169E1). oklch(55% 0.198 264.1), rgb(51, 102, 227).
Aa
White text reads best on this color (5.05:1).
About this color
#3366E3 is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.198 and its hue 264°. 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 5.05:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.198) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.15:1 |
| White text | 5.05:1 |
Values
| HEX | #3366E3 |
| RGB | rgb(51, 102, 227) |
| HSL | hsl(223, 76%, 55%) |
| OKLCH | oklch(55% 0.198 264.1) |
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 #3366E3 | 5.05:1 | AA | Lc -79.8 | Fine for body text |
| Black text on #3366E3 | 4.15:1 | AA large text | Lc 29.7 | Dividers and decoration only |
| #3366E3 text on white | 5.05:1 | AA | Lc 74.4 | Content text, not long reading |
| #3366E3 text on black | 4.15:1 | AA large text | Lc -27.3 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E1EAFC
oklch(93.6% 0.026 264.4)
-
Step 200
200
#C9DAFB
oklch(88.6% 0.049 263.7)
-
Step 300
300
#A4C0FB
oklch(80.8% 0.089 264.8)
-
Step 400
400
#739EF9
oklch(70.8% 0.142 264)
-
Step 500
500
#4F82F6
oklch(63.1% 0.182 264)
-
Step 600
600 (this color)
#3366E3
oklch(55% 0.198 264.1)
-
Step 700
700
#2856C7
oklch(49.2% 0.184 264)
-
Step 800
800
#2247A1
oklch(42.8% 0.152 264.1)
-
Step 900
900
#203D80
oklch(37.8% 0.119 264)
-
Step 950
950
#13244B
oklch(27% 0.076 264.2)
#3366E3 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) | #0077E7 | 0.043 |
| Deuteranopia (no green cones) | #0067E1 | 0.023 |
| Tritanopia (no blue cones) | #00859B | 0.154 |
| Achromatopsia (no color) | #6F6F6F | 0.198 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3366E3
#3366E3
oklch(55% 0.198 264.1)
- #906B00
#906B00
oklch(55% 0.113 84.6)
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 #3366E3, 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 0.024
- Cerulean Blue #056EEE ΔE 0.028
- Azul #1D5DEC ΔE 0.031
- Warm Blue #4B57DB ΔE 0.040
- Bright Blue #0165FC ΔE 0.043
- Clear Blue #247AFD ΔE 0.060
- Dark Periwinkle #665FD1 ΔE 0.064
Use #3366E3 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.