#6566D7
Closest named color: Dark Periwinkle (#665FD1). oklch(56.8% 0.169 279.2), rgb(101, 102, 215).
Aa
White text reads best on this color (4.73:1).
About this color
#6566D7 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.169 and its hue 279°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.018 away. White text reads best on it, at 4.73:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.169) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.43:1 |
| White text | 4.73:1 |
Values
| HEX | #6566D7 |
| RGB | rgb(101, 102, 215) |
| HSL | hsl(239, 59%, 62%) |
| OKLCH | oklch(56.8% 0.169 279.2) |
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 #6566D7 | 4.73:1 | AA | Lc -78.0 | Fine for body text |
| Black text on #6566D7 | 4.43:1 | AA large text | Lc 31.5 | Non-text elements, placeholder text |
| #6566D7 text on white | 4.73:1 | AA | Lc 72.6 | Content text, not long reading |
| #6566D7 text on black | 4.43:1 | AA large text | Lc -29.1 | 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
#F4F5FC
oklch(97.1% 0.009 279.7)
-
Step 100
100
#E6E9F9
oklch(93.6% 0.022 277.5)
-
Step 200
200
#D3D7F5
oklch(88.5% 0.041 279.5)
-
Step 300
300
#B6BCF2
oklch(80.9% 0.076 279.6)
-
Step 400
400
#9198EB
oklch(70.8% 0.121 279.1)
-
Step 500
500
#777CE5
oklch(63.1% 0.155 278.9)
-
Step 600
600 (this color)
#6566D7
oklch(56.8% 0.169 279.2)
-
Step 700
700
#5151B7
oklch(49.2% 0.157 278.9)
-
Step 800
800
#424394
oklch(42.8% 0.13 278.8)
-
Step 900
900
#373976
oklch(37.6% 0.102 278.9)
-
Step 950
950
#202245
oklch(27% 0.064 278.7)
#6566D7 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) | #2778DB | 0.069 |
| Deuteranopia (no green cones) | #146FD5 | 0.072 |
| Tritanopia (no blue cones) | #327F95 | 0.146 |
| Achromatopsia (no color) | #737373 | 0.170 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #6566D7
#6566D7
oklch(56.8% 0.169 279.2)
- #887700
#887700
oklch(56.8% 0.118 99.3)
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 #6566D7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.018
- Light Indigo #6D5ACF ΔE 0.031
- Slate Blue #6A5ACD ΔE 0.031
- Iris #6258C4 ΔE 0.043
- Royal Blue #4169E1 ΔE 0.045
- Medium Slate Blue #7B68EE ΔE 0.048
- Warm Blue #4B57DB ΔE 0.054
- Neon Blue #4361EE ΔE 0.057
Use #6566D7 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.