#6B66C8
Closest named color: Dark Periwinkle (#665FD1). oklch(56.3% 0.148 282.9), rgb(107, 102, 200).
Aa
White text reads best on this color (4.81:1).
About this color
#6B66C8 is a medium-dark, vivid purple. In OKLCH its lightness is 56%, its chroma 0.148 and its hue 283°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.025 away. White text reads best on it, at 4.81:1.
| Hue family | Purples |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.148) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.35:1 |
| White text | 4.81:1 |
Values
| HEX | #6B66C8 |
| RGB | rgb(107, 102, 200) |
| HSL | hsl(243, 47%, 59%) |
| OKLCH | oklch(56.3% 0.148 282.9) |
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 #6B66C8 | 4.81:1 | AA | Lc -78.7 | Fine for body text |
| Black text on #6B66C8 | 4.35:1 | AA large text | Lc 30.9 | Non-text elements, placeholder text |
| #6B66C8 text on white | 4.81:1 | AA | Lc 73.2 | Content text, not long reading |
| #6B66C8 text on black | 4.35:1 | AA large text | Lc -28.5 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E8E9F7
oklch(93.7% 0.019 282.8)
-
Step 200
200
#D5D7F2
oklch(88.6% 0.037 282.2)
-
Step 300
300
#BABCEB
oklch(81% 0.066 282.9)
-
Step 400
400
#9798E1
oklch(70.7% 0.106 282.7)
-
Step 500
500
#7F7DD8
oklch(63.2% 0.135 282.8)
-
Step 600
600 (this color)
#6B66C8
oklch(56.3% 0.148 282.9)
-
Step 700
700
#5852AB
oklch(49% 0.138 283.1)
-
Step 800
800
#48448A
oklch(42.7% 0.113 283.1)
-
Step 900
900
#3C3A6F
oklch(37.8% 0.089 283)
-
Step 950
950
#232241
oklch(27% 0.057 283.4)
#6B66C8 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) | #3B75CC | 0.063 |
| Deuteranopia (no green cones) | #366FC6 | 0.063 |
| Tritanopia (no blue cones) | #4B7B8D | 0.128 |
| Achromatopsia (no color) | #727272 | 0.148 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #6B66C8
#6B66C8
oklch(56.3% 0.148 282.9)
- #837700
#837700
oklch(56.3% 0.118 102.4)
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 #6B66C8, closest first.
No curated palette has a color within ΔE 0.04 of #6B66C8.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.025
- Slate Blue #6A5ACD ΔE 0.031
- Light Indigo #6D5ACF ΔE 0.032
- Iris #6258C4 ΔE 0.039
- Deep Lavender #8D5EB7 ΔE 0.061
- Royal Blue #4169E1 ΔE 0.063
- Medium Slate Blue #7B68EE ΔE 0.063
- Warm Blue #4B57DB ΔE 0.069
Use #6B66C8 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.