#5566F0
Closest named color: Neon Blue (#4361EE). oklch(57.6% 0.206 272.8), rgb(85, 102, 240).
Aa
White text reads best on this color (4.62:1).
About this color
#5566F0 is a medium-dark, vivid blue. In OKLCH its lightness is 58%, its chroma 0.206 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Neon Blue (#4361EE), ΔE 0.026 away. White text reads best on it, at 4.62:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | vivid (0.206) |
| Temperature | cool |
| Nearest name | Neon Blue (#4361EE) |
| Black text | 4.54:1 |
| White text | 4.62:1 |
Values
| HEX | #5566F0 |
| RGB | rgb(85, 102, 240) |
| HSL | hsl(233, 84%, 64%) |
| OKLCH | oklch(57.6% 0.206 272.8) |
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 #5566F0 | 4.62:1 | AA | Lc -77.1 | Fine for body text |
| Black text on #5566F0 | 4.54:1 | AA | Lc 32.5 | Non-text elements, placeholder text |
| #5566F0 text on white | 4.62:1 | AA | Lc 71.6 | Content text, not long reading |
| #5566F0 text on black | 4.54:1 | AA | Lc -30.0 | Non-text elements, placeholder text |
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
#E4E9FC
oklch(93.6% 0.026 274.1)
-
Step 200
200
#CDD8FC
oklch(88.5% 0.051 271.9)
-
Step 300
300
#ACBDFD
oklch(80.9% 0.093 272.7)
-
Step 400
400
#8298FC
oklch(70.6% 0.148 272.7)
-
Step 500
500
#667BFA
oklch(63.2% 0.189 272.8)
-
Step 600
600 (this color)
#5566F0
oklch(57.6% 0.206 272.8)
-
Step 700
700
#414ECB
oklch(49.2% 0.192 272.6)
-
Step 800
800
#3541A4
oklch(42.8% 0.159 272.5)
-
Step 900
900
#2E3882
oklch(37.7% 0.124 273.1)
-
Step 950
950
#1A224C
oklch(27.1% 0.078 272.1)
#5566F0 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) | #007CF5 | 0.065 |
| Deuteranopia (no green cones) | #006EED | 0.055 |
| Tritanopia (no blue cones) | #0088A1 | 0.171 |
| Achromatopsia (no color) | #757575 | 0.206 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5566F0
#5566F0
oklch(57.6% 0.206 272.8)
- #917600
#917600
oklch(57.5% 0.118 92.8)
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 #5566F0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Neon Blue #4361EE ΔE 0.026
- Royal Blue #4169E1 ΔE 0.033
- Warm Blue #4B57DB ΔE 0.050
- Dark Periwinkle #665FD1 ΔE 0.053
- Cerulean Blue #056EEE ΔE 0.053
- Medium Slate Blue #7B68EE ΔE 0.054
- Cornflower #6A79F7 ΔE 0.056
- Clear Blue #247AFD ΔE 0.057
Use #5566F0 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.