#6570CB
Closest named color: Dark Periwinkle (#665FD1). oklch(57.9% 0.139 276), rgb(101, 112, 203).
Aa
Black text reads best on this color (4.73:1).
About this color
#6570CB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.139 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.045 away. Black text reads best on it, at 4.73:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.139) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.73:1 |
| White text | 4.43:1 |
Values
| HEX | #6570CB |
| RGB | rgb(101, 112, 203) |
| HSL | hsl(234, 50%, 60%) |
| OKLCH | oklch(57.9% 0.139 276) |
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 #6570CB | 4.43:1 | AA large text | Lc -76.1 | Fine for body text |
| Black text on #6570CB | 4.73:1 | AA | Lc 33.5 | Non-text elements, placeholder text |
| #6570CB text on white | 4.43:1 | AA large text | Lc 70.6 | Content text, not long reading |
| #6570CB text on black | 4.73:1 | AA | Lc -31.1 | 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 600.
-
Step 50
50
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E6E9F6
oklch(93.6% 0.018 275.6)
-
Step 200
200
#D2D8F1
oklch(88.5% 0.035 274.9)
-
Step 300
300
#B5BEEA
oklch(80.9% 0.063 275.9)
-
Step 400
400
#8F9BDF
oklch(70.6% 0.101 275.8)
-
Step 500
500
#7581D6
oklch(63.1% 0.128 276)
-
Step 600
600 (this color)
#6570CB
oklch(57.9% 0.139 276)
-
Step 700
700
#4E57A9
oklch(49.1% 0.13 275.8)
-
Step 800
800
#404789
oklch(42.6% 0.108 276.2)
-
Step 900
900
#363C6D
oklch(37.6% 0.084 276.3)
-
Step 950
950
#202440
oklch(27.1% 0.052 276.2)
#6570CB 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) | #4A7CCE | 0.040 |
| Deuteranopia (no green cones) | #4074C9 | 0.042 |
| Tritanopia (no blue cones) | #3B8394 | 0.121 |
| Achromatopsia (no color) | #787878 | 0.139 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #6570CB
#6570CB
oklch(57.9% 0.139 276)
- #8F7900
#8F7900
oklch(57.9% 0.119 96.3)
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 #6570CB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.045
- Slate Blue #6A5ACD ΔE 0.055
- Light Indigo #6D5ACF ΔE 0.055
- Windows Blue #3778BF ΔE 0.057
- Royal Blue #4169E1 ΔE 0.059
- Iris #6258C4 ΔE 0.061
- French Blue #436BAD ΔE 0.066
- Medium Slate Blue #7B68EE ΔE 0.066
Use #6570CB 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.