#645DD6
Closest named color: Dark Periwinkle (#665FD1). oklch(55% 0.18 281.3), rgb(100, 93, 214).
Aa
White text reads best on this color (5.14:1).
About this color
#645DD6 is a medium-dark, vivid purple. In OKLCH its lightness is 55%, its chroma 0.180 and its hue 281°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.010 away. White text reads best on it, at 5.14:1.
| Hue family | Purples |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.180) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.07:1 |
| White text | 5.14:1 |
Values
| HEX | #645DD6 |
| RGB | rgb(100, 93, 214) |
| HSL | hsl(243, 60%, 60%) |
| OKLCH | oklch(55% 0.18 281.3) |
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 #645DD6 | 5.14:1 | AA | Lc -80.5 | Fine for body text |
| Black text on #645DD6 | 4.07:1 | AA large text | Lc 28.9 | Dividers and decoration only |
| #645DD6 text on white | 5.14:1 | AA | Lc 75.1 | Fine for body text |
| #645DD6 text on black | 4.07:1 | AA large text | Lc -26.6 | 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 600.
-
Step 50
50
#F4F5FD
oklch(97.2% 0.011 280.5)
-
Step 100
100
#E7E8FA
oklch(93.6% 0.024 283.4)
-
Step 200
200
#D3D6F7
oklch(88.4% 0.045 281.3)
-
Step 300
300
#B7BBF4
oklch(80.9% 0.08 281.3)
-
Step 400
400
#9396EF
oklch(70.7% 0.129 281.1)
-
Step 500
500
#7B79EA
oklch(63.2% 0.166 281.4)
-
Step 600
600 (this color)
#645DD6
oklch(55% 0.18 281.3)
-
Step 700
700
#554DBB
oklch(49.1% 0.167 281.6)
-
Step 800
800
#454097
oklch(42.6% 0.138 281.4)
-
Step 900
900
#393779
oklch(37.6% 0.109 281.1)
-
Step 950
950
#212147
oklch(27% 0.069 280.7)
#645DD6 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) | #0072DA | 0.084 |
| Deuteranopia (no green cones) | #0069D3 | 0.081 |
| Tritanopia (no blue cones) | #327990 | 0.155 |
| Achromatopsia (no color) | #6D6D6D | 0.181 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #645DD6
#645DD6
oklch(55% 0.18 281.3)
- #807300
#807300
oklch(55% 0.115 101.5)
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 #645DD6, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.010
- Slate Blue #6A5ACD ΔE 0.017
- Light Indigo #6D5ACF ΔE 0.018
- Iris #6258C4 ΔE 0.030
- Warm Blue #4B57DB ΔE 0.040
- Royal Blue #4169E1 ΔE 0.049
- Neon Blue #4361EE ΔE 0.054
- Medium Slate Blue #7B68EE ΔE 0.057
Use #645DD6 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.