#5166DA
Closest named color: Royal Blue (#4169E1). oklch(55.7% 0.178 271.7), rgb(81, 102, 218).
Aa
White text reads best on this color (4.92:1).
About this color
#5166DA is a medium-dark, vivid blue. In OKLCH its lightness is 56%, its chroma 0.178 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.020 away. White text reads best on it, at 4.92:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.178) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.26:1 |
| White text | 4.92:1 |
Values
| HEX | #5166DA |
| RGB | rgb(81, 102, 218) |
| HSL | hsl(231, 65%, 59%) |
| OKLCH | oklch(55.7% 0.178 271.7) |
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 #5166DA | 4.92:1 | AA | Lc -79.2 | Fine for body text |
| Black text on #5166DA | 4.26:1 | AA large text | Lc 30.3 | Non-text elements, placeholder text |
| #5166DA text on white | 4.92:1 | AA | Lc 73.8 | Content text, not long reading |
| #5166DA text on black | 4.26:1 | AA large text | Lc -27.9 | 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
#E4E9FA
oklch(93.5% 0.024 272.8)
-
Step 200
200
#CED8F7
oklch(88.4% 0.044 271.3)
-
Step 300
300
#AEBEF5
oklch(80.9% 0.08 271.9)
-
Step 400
400
#849BF0
oklch(70.7% 0.127 271.3)
-
Step 500
500
#677FEB
oklch(63% 0.164 271.6)
-
Step 600
600 (this color)
#5166DA
oklch(55.7% 0.178 271.7)
-
Step 700
700
#4254BD
oklch(49.2% 0.165 271.6)
-
Step 800
800
#364599
oklch(42.7% 0.138 271.7)
-
Step 900
900
#2E3B79
oklch(37.6% 0.106 271.5)
-
Step 950
950
#1B2347
oklch(27% 0.068 271.8)
#5166DA 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) | #1777DE | 0.055 |
| Deuteranopia (no green cones) | #006BD8 | 0.052 |
| Tritanopia (no blue cones) | #008196 | 0.150 |
| Achromatopsia (no color) | #707070 | 0.178 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5166DA
#5166DA
oklch(55.7% 0.178 271.7)
- #8C7000
#8C7000
oklch(55.6% 0.114 91.4)
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 #5166DA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.020
- Dark Periwinkle #665FD1 ΔE 0.033
- Neon Blue #4361EE ΔE 0.037
- Warm Blue #4B57DB ΔE 0.038
- Slate Blue #6A5ACD ΔE 0.045
- Light Indigo #6D5ACF ΔE 0.047
- Iris #6258C4 ΔE 0.049
- Cerulean Blue #056EEE ΔE 0.056
Use #5166DA 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.