#5166EF
Closest named color: Neon Blue (#4361EE). oklch(57.3% 0.206 271.7), rgb(81, 102, 239).
Aa
White text reads best on this color (4.66:1).
About this color
#5166EF is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.206 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Neon Blue (#4361EE), ΔE 0.021 away. White text reads best on it, at 4.66:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.206) |
| Temperature | cool |
| Nearest name | Neon Blue (#4361EE) |
| Black text | 4.49:1 |
| White text | 4.66:1 |
Values
| HEX | #5166EF |
| RGB | rgb(81, 102, 239) |
| HSL | hsl(232, 83%, 63%) |
| OKLCH | oklch(57.3% 0.206 271.7) |
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 #5166EF | 4.66:1 | AA | Lc -77.4 | Fine for body text |
| Black text on #5166EF | 4.49:1 | AA large text | Lc 32.1 | Non-text elements, placeholder text |
| #5166EF text on white | 4.66:1 | AA | Lc 72.0 | Content text, not long reading |
| #5166EF text on black | 4.49:1 | AA large text | Lc -29.7 | 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
#CDD8FC
oklch(88.5% 0.051 271.9)
-
Step 300
300
#ABBEFD
oklch(81% 0.092 271.3)
-
Step 400
400
#8099FC
oklch(70.7% 0.148 271.5)
-
Step 500
500
#637CFA
oklch(63.2% 0.189 271.6)
-
Step 600
600 (this color)
#5166EF
oklch(57.3% 0.206 271.7)
-
Step 700
700
#3E4FCB
oklch(49.2% 0.191 271.4)
-
Step 800
800
#3341A4
oklch(42.6% 0.159 271.7)
-
Step 900
900
#2C3982
oklch(37.8% 0.123 271.6)
-
Step 950
950
#19224C
oklch(27% 0.078 271.2)
#5166EF 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) | #007BF4 | 0.061 |
| Deuteranopia (no green cones) | #006DEC | 0.050 |
| Tritanopia (no blue cones) | #0088A1 | 0.169 |
| Achromatopsia (no color) | #747474 | 0.206 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5166EF
#5166EF
oklch(57.3% 0.206 271.7)
- #917500
#917500
oklch(57.3% 0.117 92.1)
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 #5166EF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Neon Blue #4361EE ΔE 0.021
- Royal Blue #4169E1 ΔE 0.028
- Warm Blue #4B57DB ΔE 0.047
- Cerulean Blue #056EEE ΔE 0.049
- Dark Periwinkle #665FD1 ΔE 0.053
- Azul #1D5DEC ΔE 0.054
- Bright Blue #0165FC ΔE 0.055
- Clear Blue #247AFD ΔE 0.055
Use #5166EF 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.