#645BE4
Closest named color: Dark Periwinkle (#665FD1). oklch(55.8% 0.201 280.6), rgb(100, 91, 228).
Aa
White text reads best on this color (5.04:1).
About this color
#645BE4 is a medium-dark, vivid purple. In OKLCH its lightness is 56%, its chroma 0.201 and its hue 281°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.031 away. White text reads best on it, at 5.04:1.
| Hue family | Purples |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.201) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.15:1 |
| White text | 5.04:1 |
Values
| HEX | #645BE4 |
| RGB | rgb(100, 91, 228) |
| HSL | hsl(244, 72%, 63%) |
| OKLCH | oklch(55.8% 0.201 280.6) |
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 #645BE4 | 5.04:1 | AA | Lc -79.8 | Fine for body text |
| Black text on #645BE4 | 4.15:1 | AA large text | Lc 29.6 | Dividers and decoration only |
| #645BE4 text on white | 5.04:1 | AA | Lc 74.4 | Content text, not long reading |
| #645BE4 text on black | 4.15:1 | AA large text | Lc -27.3 | 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
#F4F5FE
oklch(97.2% 0.012 281.1)
-
Step 100
100
#E6E8FC
oklch(93.5% 0.027 281.3)
-
Step 200
200
#D2D6FA
oklch(88.4% 0.05 280.3)
-
Step 300
300
#B5BAFA
oklch(80.8% 0.09 280.7)
-
Step 400
400
#9194F8
oklch(70.7% 0.145 280.7)
-
Step 500
500
#7876F5
oklch(63.1% 0.185 280.4)
-
Step 600
600 (this color)
#645BE4
oklch(55.8% 0.201 280.6)
-
Step 700
700
#5349C6
oklch(49.1% 0.187 280.6)
-
Step 800
800
#443DA0
oklch(42.7% 0.155 280.8)
-
Step 900
900
#38357F
oklch(37.6% 0.121 280.6)
-
Step 950
950
#21204A
oklch(27% 0.076 281.1)
#645BE4 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) | #0074E8 | 0.086 |
| Deuteranopia (no green cones) | #006AE1 | 0.080 |
| Tritanopia (no blue cones) | #1E7C97 | 0.172 |
| Achromatopsia (no color) | #6F6F6F | 0.201 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #645BE4
#645BE4
oklch(55.8% 0.201 280.6)
- #837500
#837500
oklch(55.8% 0.116 101)
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 #645BE4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.031
- Light Indigo #6D5ACF ΔE 0.035
- Slate Blue #6A5ACD ΔE 0.036
- Warm Blue #4B57DB ΔE 0.040
- Neon Blue #4361EE ΔE 0.044
- Iris #6258C4 ΔE 0.049
- Royal Blue #4169E1 ΔE 0.050
- Medium Slate Blue #7B68EE ΔE 0.050
Use #645BE4 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.