#5A66E3
Closest named color: Royal Blue (#4169E1). oklch(56.9% 0.188 274.6), rgb(90, 102, 227).
Aa
White text reads best on this color (4.72:1).
About this color
#5A66E3 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.188 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.029 away. White text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.188) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.44:1 |
| White text | 4.72:1 |
Values
| HEX | #5A66E3 |
| RGB | rgb(90, 102, 227) |
| HSL | hsl(235, 71%, 62%) |
| OKLCH | oklch(56.9% 0.188 274.6) |
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 #5A66E3 | 4.72:1 | AA | Lc -77.9 | Fine for body text |
| Black text on #5A66E3 | 4.44:1 | AA large text | Lc 31.6 | Non-text elements, placeholder text |
| #5A66E3 text on white | 4.72:1 | AA | Lc 72.4 | Content text, not long reading |
| #5A66E3 text on black | 4.44:1 | AA large text | Lc -29.2 | 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
#E5E9FB
oklch(93.6% 0.025 275.9)
-
Step 200
200
#CFD7F9
oklch(88.4% 0.048 274.9)
-
Step 300
300
#B0BDF8
oklch(80.9% 0.085 274.7)
-
Step 400
400
#8899F4
oklch(70.8% 0.134 274.4)
-
Step 500
500
#6D7CF0
oklch(63.1% 0.173 274.8)
-
Step 600
600 (this color)
#5A66E3
oklch(56.9% 0.188 274.6)
-
Step 700
700
#4750C1
oklch(49.1% 0.174 274.5)
-
Step 800
800
#3A429C
oklch(42.6% 0.145 274.6)
-
Step 900
900
#31397C
oklch(37.6% 0.113 274.5)
-
Step 950
950
#1D2249
oklch(27% 0.072 275)
#5A66E3 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 | 0.067 |
| Deuteranopia (no green cones) | #006DE0 | 0.062 |
| Tritanopia (no blue cones) | #00849B | 0.161 |
| Achromatopsia (no color) | #737373 | 0.188 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5A66E3
#5A66E3
oklch(56.9% 0.188 274.6)
- #8D7500
#8D7500
oklch(56.8% 0.117 94.6)
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 #5A66E3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.029
- Dark Periwinkle #665FD1 ΔE 0.034
- Neon Blue #4361EE ΔE 0.035
- Warm Blue #4B57DB ΔE 0.044
- Slate Blue #6A5ACD ΔE 0.046
- Light Indigo #6D5ACF ΔE 0.046
- Medium Slate Blue #7B68EE ΔE 0.051
- Iris #6258C4 ΔE 0.056
Use #5A66E3 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.