#664EB3
Closest named color: Iris (#6258C4). oklch(50.1% 0.154 290.7), rgb(102, 78, 179).
Aa
White text reads best on this color (6.35:1).
About this color
#664EB3 is a medium-dark, vivid purple. In OKLCH its lightness is 50%, its chroma 0.154 and its hue 291°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Iris (#6258C4), ΔE 0.034 away. White text reads best on it, at 6.35:1.
| Hue family | Purples |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.154) |
| Temperature | in between |
| Nearest name | Iris (#6258C4) |
| Black text | 3.30:1 |
| White text | 6.35:1 |
Values
| HEX | #664EB3 |
| RGB | rgb(102, 78, 179) |
| HSL | hsl(254, 40%, 50%) |
| OKLCH | oklch(50.1% 0.154 290.7) |
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 #664EB3 | 6.35:1 | AA | Lc -86.4 | Fine for body text |
| Black text on #664EB3 | 3.30:1 | AA large text | Lc 22.8 | Dividers and decoration only |
| #664EB3 text on white | 6.35:1 | AA | Lc 81.3 | Fine for body text |
| #664EB3 text on black | 3.30:1 | AA large text | Lc -20.6 | 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 700.
-
Step 50
50
#F5F4FC
oklch(97% 0.011 292)
-
Step 100
100
#E9E8F8
oklch(93.6% 0.021 288.9)
-
Step 200
200
#D8D5F3
oklch(88.5% 0.041 290.1)
-
Step 300
300
#C0B9EE
oklch(81% 0.074 290.7)
-
Step 400
400
#A193E5
oklch(70.8% 0.118 290.9)
-
Step 500
500
#8B76DD
oklch(63.1% 0.151 290.8)
-
Step 600
600
#765CCB
oklch(55.6% 0.165 290.8)
-
Step 700
700 (this color)
#664EB3
oklch(50.1% 0.154 290.7)
-
Step 800
800
#513E8E
oklch(42.7% 0.127 291)
-
Step 900
900
#433672
oklch(37.8% 0.099 290.8)
-
Step 950
950
#272043
oklch(27.1% 0.064 290.7)
#664EB3 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) | #1661B6 | 0.093 |
| Deuteranopia (no green cones) | #1C5DB1 | 0.089 |
| Tritanopia (no blue cones) | #506479 | 0.125 |
| Achromatopsia (no color) | #5F5F5F | 0.155 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #664EB3
#664EB3
oklch(50.1% 0.154 290.7)
- #676900
#676900
oklch(50.2% 0.11 111.1)
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 #664EB3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Iris #6258C4 ΔE 0.034
- Bluey Purple #6241C7 ΔE 0.044
- Slate Blue #6A5ACD ΔE 0.048
- Light Indigo #6D5ACF ΔE 0.052
- Dark Periwinkle #665FD1 ΔE 0.059
- Blue With A Hint Of Purple #533CC6 ΔE 0.062
- Blurple #5539CC ΔE 0.069
- Rebecca Purple #663399 ΔE 0.070
Use #664EB3 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.