#5866CB
Closest named color: Dark Periwinkle (#665FD1). oklch(55.1% 0.156 274.2), rgb(88, 102, 203).
Aa
White text reads best on this color (5.02:1).
About this color
#5866CB is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.156 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.027 away. White text reads best on it, at 5.02:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.156) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.17:1 |
| White text | 5.02:1 |
Values
| HEX | #5866CB |
| RGB | rgb(88, 102, 203) |
| HSL | hsl(233, 53%, 57%) |
| OKLCH | oklch(55.1% 0.156 274.2) |
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 #5866CB | 5.02:1 | AA | Lc -79.9 | Fine for body text |
| Black text on #5866CB | 4.17:1 | AA large text | Lc 29.6 | Dividers and decoration only |
| #5866CB text on white | 5.02:1 | AA | Lc 74.5 | Content text, not long reading |
| #5866CB text on black | 4.17:1 | AA large text | Lc -27.2 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E5E9F8
oklch(93.5% 0.021 274)
-
Step 200
200
#D1D8F4
oklch(88.6% 0.039 274.4)
-
Step 300
300
#B2BEEF
oklch(80.9% 0.071 274)
-
Step 400
400
#8B9BE6
oklch(70.7% 0.111 274)
-
Step 500
500
#7080DF
oklch(63.1% 0.143 274.4)
-
Step 600
600 (this color)
#5866CB
oklch(55.1% 0.156 274.2)
-
Step 700
700
#4A56B1
oklch(49.2% 0.144 274.2)
-
Step 800
800
#3C468F
oklch(42.6% 0.12 274.3)
-
Step 900
900
#333C72
oklch(37.7% 0.092 274)
-
Step 950
950
#1E2343
oklch(26.9% 0.06 275)
#5866CB 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) | #3274CF | 0.048 |
| Deuteranopia (no green cones) | #1F6AC9 | 0.053 |
| Tritanopia (no blue cones) | #117D8F | 0.138 |
| Achromatopsia (no color) | #6F6F6F | 0.156 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5866CB
#5866CB
oklch(55.1% 0.156 274.2)
- #877000
#877000
oklch(55.1% 0.113 94.7)
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 #5866CB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.027
- Iris #6258C4 ΔE 0.036
- Slate Blue #6A5ACD ΔE 0.037
- Light Indigo #6D5ACF ΔE 0.040
- Royal Blue #4169E1 ΔE 0.041
- Warm Blue #4B57DB ΔE 0.050
- French Blue #436BAD ΔE 0.057
- Windows Blue #3778BF ΔE 0.061
Use #5866CB 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.