#5166E9
Closest named color: Royal Blue (#4169E1). oklch(56.8% 0.198 271.7), rgb(81, 102, 233).
Aa
White text reads best on this color (4.74:1).
About this color
#5166E9 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.198 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.022 away. White text reads best on it, at 4.74:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.198) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.42:1 |
| White text | 4.74:1 |
Values
| HEX | #5166E9 |
| RGB | rgb(81, 102, 233) |
| HSL | hsl(232, 78%, 62%) |
| OKLCH | oklch(56.8% 0.198 271.7) |
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 #5166E9 | 4.74:1 | AA | Lc -77.9 | Fine for body text |
| Black text on #5166E9 | 4.42:1 | AA large text | Lc 31.6 | Non-text elements, placeholder text |
| #5166E9 text on white | 4.74:1 | AA | Lc 72.5 | Content text, not long reading |
| #5166E9 text on black | 4.42:1 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FC
oklch(93.5% 0.027 271.9)
-
Step 200
200
#CDD8FB
oklch(88.5% 0.05 271.6)
-
Step 300
300
#ACBEFB
oklch(81% 0.089 271.6)
-
Step 400
400
#8199F9
oklch(70.6% 0.143 271.7)
-
Step 500
500
#647DF6
oklch(63.2% 0.182 271.5)
-
Step 600
600 (this color)
#5166E9
oklch(56.8% 0.198 271.7)
-
Step 700
700
#3F50C7
oklch(49.1% 0.185 271.6)
-
Step 800
800
#3442A1
oklch(42.6% 0.153 271.9)
-
Step 900
900
#2D3980
oklch(37.7% 0.12 272.1)
-
Step 950
950
#1A224B
oklch(27% 0.076 272.1)
#5166E9 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) | #007AED | 0.060 |
| Deuteranopia (no green cones) | #006CE6 | 0.051 |
| Tritanopia (no blue cones) | #00869E | 0.163 |
| Achromatopsia (no color) | #737373 | 0.198 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5166E9
#5166E9
oklch(56.8% 0.198 271.7)
- #907400
#907400
oklch(57% 0.116 91.9)
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 #5166E9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.022
- Neon Blue #4361EE ΔE 0.023
- Warm Blue #4B57DB ΔE 0.042
- Dark Periwinkle #665FD1 ΔE 0.046
- Cerulean Blue #056EEE ΔE 0.049
- Azul #1D5DEC ΔE 0.054
- Slate Blue #6A5ACD ΔE 0.057
- Light Indigo #6D5ACF ΔE 0.058
Use #5166E9 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.