#646DEB
Closest named color: Medium Slate Blue (#7B68EE). oklch(59.4% 0.187 276), rgb(100, 109, 235).
Aa
Black text reads best on this color (4.92:1).
About this color
#646DEB is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.187 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Medium Slate Blue (#7B68EE), ΔE 0.034 away. Black text reads best on it, at 4.92:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.187) |
| Temperature | cool |
| Nearest name | Medium Slate Blue (#7B68EE) |
| Black text | 4.92:1 |
| White text | 4.26:1 |
Values
| HEX | #646DEB |
| RGB | rgb(100, 109, 235) |
| HSL | hsl(236, 77%, 66%) |
| OKLCH | oklch(59.4% 0.187 276) |
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 #646DEB | 4.26:1 | AA large text | Lc -74.6 | Content text, not long reading |
| Black text on #646DEB | 4.92:1 | AA | Lc 35.0 | Non-text elements, placeholder text |
| #646DEB text on white | 4.26:1 | AA large text | Lc 69.1 | Content text, not long reading |
| #646DEB text on black | 4.92:1 | AA | Lc -32.6 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E5E9FC
oklch(93.7% 0.026 276.4)
-
Step 200
200
#CFD7FB
oklch(88.5% 0.05 275.4)
-
Step 300
300
#B0BCFC
oklch(80.9% 0.092 275.9)
-
Step 400
400
#8996FB
oklch(70.7% 0.148 276.4)
-
Step 500
500 (this color)
#646DEB
oklch(59.4% 0.187 276)
-
Step 600
600
#595DE7
oklch(55.6% 0.204 276.2)
-
Step 700
700
#494CC9
oklch(49.1% 0.19 275.8)
-
Step 800
800
#3C3FA2
oklch(42.7% 0.157 276.2)
-
Step 900
900
#323781
oklch(37.7% 0.123 275.9)
-
Step 950
950
#1D214B
oklch(27% 0.077 275.9)
#646DEB 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) | #1A80EF | 0.069 |
| Deuteranopia (no green cones) | #0075E8 | 0.070 |
| Tritanopia (no blue cones) | #008AA1 | 0.165 |
| Achromatopsia (no color) | #7B7B7B | 0.188 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646DEB
#646DEB
oklch(59.4% 0.187 276)
- #947D00
#947D00
oklch(59.3% 0.122 96.1)
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 #646DEB, closest first.
No curated palette has a color within ΔE 0.04 of #646DEB.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Medium Slate Blue #7B68EE ΔE 0.034
- Cornflower #6A79F7 ΔE 0.035
- Royal Blue #4169E1 ΔE 0.047
- Dark Periwinkle #665FD1 ΔE 0.049
- Neon Blue #4361EE ΔE 0.053
- Light Indigo #6D5ACF ΔE 0.059
- Slate Blue #6A5ACD ΔE 0.061
- Clear Blue #247AFD ΔE 0.063
Use #646DEB 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.