#5666E3
Closest named color: Royal Blue (#4169E1). oklch(56.7% 0.189 273.3), rgb(86, 102, 227).
Aa
White text reads best on this color (4.76:1).
About this color
#5666E3 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.189 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.024 away. White text reads best on it, at 4.76:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.189) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.40:1 |
| White text | 4.76:1 |
Values
| HEX | #5666E3 |
| RGB | rgb(86, 102, 227) |
| HSL | hsl(233, 72%, 61%) |
| OKLCH | oklch(56.7% 0.189 273.3) |
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 #5666E3 | 4.76:1 | AA | Lc -78.1 | Fine for body text |
| Black text on #5666E3 | 4.40:1 | AA large text | Lc 31.4 | Non-text elements, placeholder text |
| #5666E3 text on white | 4.76:1 | AA | Lc 72.7 | Content text, not long reading |
| #5666E3 text on black | 4.40:1 | AA large text | Lc -29.0 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E4E9FB
oklch(93.6% 0.025 273.5)
-
Step 200
200
#CFD8F9
oklch(88.6% 0.047 273.4)
-
Step 300
300
#AEBDF8
oklch(80.8% 0.085 273.3)
-
Step 400
400
#8699F5
oklch(70.7% 0.136 273.6)
-
Step 500
500
#697DF1
oklch(63.1% 0.174 273.1)
-
Step 600
600 (this color)
#5666E3
oklch(56.7% 0.189 273.3)
-
Step 700
700
#4451C2
oklch(49.1% 0.175 273.1)
-
Step 800
800
#38439D
oklch(42.7% 0.145 273.3)
-
Step 900
900
#303A7D
oklch(37.9% 0.113 273.4)
-
Step 950
950
#1C2249
oklch(27% 0.072 274)
#5666E3 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) | #0079E7 | 0.064 |
| Deuteranopia (no green cones) | #006DE0 | 0.057 |
| Tritanopia (no blue cones) | #00849B | 0.159 |
| Achromatopsia (no color) | #737373 | 0.189 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5666E3
#5666E3
oklch(56.7% 0.189 273.3)
- #8E7400
#8E7400
oklch(56.7% 0.116 93.2)
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 #5666E3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.024
- Neon Blue #4361EE ΔE 0.031
- Dark Periwinkle #665FD1 ΔE 0.036
- Warm Blue #4B57DB ΔE 0.041
- Slate Blue #6A5ACD ΔE 0.048
- Light Indigo #6D5ACF ΔE 0.049
- Medium Slate Blue #7B68EE ΔE 0.056
- Cerulean Blue #056EEE ΔE 0.056
Use #5666E3 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.