#666FFC
Closest named color: Cornflower (#6A79F7). oklch(61.1% 0.207 275.7), rgb(102, 111, 252).
Aa
Black text reads best on this color (5.24:1).
About this color
#666FFC is a medium-dark, vivid blue. In OKLCH its lightness is 61%, its chroma 0.207 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower (#6A79F7), ΔE 0.027 away. Black text reads best on it, at 5.24:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | vivid (0.207) |
| Temperature | cool |
| Nearest name | Cornflower (#6A79F7) |
| Black text | 5.24:1 |
| White text | 4.00:1 |
Values
| HEX | #666FFC |
| RGB | rgb(102, 111, 252) |
| HSL | hsl(236, 96%, 69%) |
| OKLCH | oklch(61.1% 0.207 275.7) |
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 #666FFC | 4.00:1 | AA large text | Lc -72.4 | Content text, not long reading |
| Black text on #666FFC | 5.24:1 | AA | Lc 37.1 | Non-text elements, placeholder text |
| #666FFC text on white | 4.00:1 | AA large text | Lc 66.9 | Content text, not long reading |
| #666FFC text on black | 5.24:1 | AA | Lc -34.7 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F3F5FF
oklch(97.2% 0.013 277.1)
-
Step 100
100
#E4E9FE
oklch(93.7% 0.029 275.2)
-
Step 200
200
#CED7FF
oklch(88.5% 0.056 275.2)
-
Step 300
300
#AFBCFF
oklch(80.9% 0.096 275.6)
-
Step 400
400
#8796FF
oklch(70.7% 0.154 275.6)
-
Step 500
500 (this color)
#666FFC
oklch(61.1% 0.207 275.7)
-
Step 600
600
#5759F3
oklch(55.7% 0.225 275.7)
-
Step 700
700
#4847D3
oklch(49.1% 0.208 275.8)
-
Step 800
800
#3A3CAB
oklch(42.8% 0.173 275.5)
-
Step 900
900
#313587
oklch(37.7% 0.135 275.7)
-
Step 950
950
#1C204F
oklch(27% 0.085 275.5)
#666FFC 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) | #0086FF | 0.077 |
| Deuteranopia (no green cones) | #0079F9 | 0.070 |
| Tritanopia (no blue cones) | #0091AB | 0.178 |
| Achromatopsia (no color) | #7F7F7F | 0.207 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #666FFC
#666FFC
oklch(61.1% 0.207 275.7)
- #9B8200
#9B8200
oklch(61.2% 0.126 95.4)
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 #666FFC, closest first.
No curated palette has a color within ΔE 0.04 of #666FFC.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cornflower #6A79F7 ΔE 0.027
- Medium Slate Blue #7B68EE ΔE 0.037
- Clear Blue #247AFD ΔE 0.060
- Neon Blue #4361EE ΔE 0.061
- Royal Blue #4169E1 ΔE 0.063
- Soft Blue #6488EA ΔE 0.070
- Dark Periwinkle #665FD1 ΔE 0.073
- Purpley #8756E4 ΔE 0.076
Use #666FFC 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.