#665DCB
Closest named color: Slate Blue (#6A5ACD). oklch(54.4% 0.165 283.1), rgb(102, 93, 203).
Aa
White text reads best on this color (5.25:1).
About this color
#665DCB is a medium-dark, vivid purple. In OKLCH its lightness is 54%, its chroma 0.165 and its hue 283°. Its hue sits on the cool side of the wheel. The nearest named color is Slate Blue (#6A5ACD), ΔE 0.009 away. White text reads best on it, at 5.25:1.
| Hue family | Purples |
| Lightness | medium-dark (54%) |
| Chroma | vivid (0.165) |
| Temperature | cool |
| Nearest name | Slate Blue (#6A5ACD) |
| Black text | 3.99:1 |
| White text | 5.25:1 |
Values
| HEX | #665DCB |
| RGB | rgb(102, 93, 203) |
| HSL | hsl(245, 51%, 58%) |
| OKLCH | oklch(54.4% 0.165 283.1) |
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 #665DCB | 5.25:1 | AA | Lc -81.2 | Fine for body text |
| Black text on #665DCB | 3.99:1 | AA large text | Lc 28.2 | Dividers and decoration only |
| #665DCB text on white | 5.25:1 | AA | Lc 75.8 | Fine for body text |
| #665DCB text on black | 3.99:1 | AA large text | Lc -25.9 | 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
#E7E8F8
oklch(93.5% 0.022 283.1)
-
Step 200
200
#D5D6F4
oklch(88.5% 0.041 284)
-
Step 300
300
#B9BBF0
oklch(80.9% 0.075 282.9)
-
Step 400
400
#9796E8
oklch(70.7% 0.119 283.5)
-
Step 500
500
#7F7AE1
oklch(63.1% 0.151 283.4)
-
Step 600
600 (this color)
#665DCB
oklch(54.4% 0.165 283.1)
-
Step 700
700
#584FB3
oklch(49.1% 0.153 283.2)
-
Step 800
800
#484191
oklch(42.6% 0.128 283.5)
-
Step 900
900
#3C3874
oklch(37.7% 0.1 283.5)
-
Step 950
950
#232144
oklch(27% 0.064 283.9)
#665DCB 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) | #1E70CF | 0.079 |
| Deuteranopia (no green cones) | #1468C9 | 0.080 |
| Tritanopia (no blue cones) | #40768B | 0.141 |
| Achromatopsia (no color) | #6C6C6C | 0.165 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #665DCB
#665DCB
oklch(54.4% 0.165 283.1)
- #7C7200
#7C7200
oklch(54.4% 0.115 103.4)
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 #665DCB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Slate Blue #6A5ACD ΔE 0.009
- Dark Periwinkle #665FD1 ΔE 0.010
- Light Indigo #6D5ACF ΔE 0.014
- Iris #6258C4 ΔE 0.017
- Warm Blue #4B57DB ΔE 0.049
- Royal Blue #4169E1 ΔE 0.059
- Bluey Purple #6241C7 ΔE 0.063
- Purpley #8756E4 ΔE 0.066
Use #665DCB 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.