#646FE0
Closest named color: Medium Slate Blue (#7B68EE). oklch(59% 0.17 275.7), rgb(100, 111, 224).
Aa
Black text reads best on this color (4.89:1).
About this color
#646FE0 is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.170 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Medium Slate Blue (#7B68EE), ΔE 0.042 away. Black text reads best on it, at 4.89:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.170) |
| Temperature | cool |
| Nearest name | Medium Slate Blue (#7B68EE) |
| Black text | 4.89:1 |
| White text | 4.29:1 |
Values
| HEX | #646FE0 |
| RGB | rgb(100, 111, 224) |
| HSL | hsl(235, 67%, 64%) |
| OKLCH | oklch(59% 0.17 275.7) |
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 #646FE0 | 4.29:1 | AA large text | Lc -74.9 | Content text, not long reading |
| Black text on #646FE0 | 4.89:1 | AA | Lc 34.7 | Non-text elements, placeholder text |
| #646FE0 text on white | 4.29:1 | AA large text | Lc 69.4 | Content text, not long reading |
| #646FE0 text on black | 4.89:1 | AA | Lc -32.2 | 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 600.
-
Step 50
50
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E5E9F9
oklch(93.6% 0.022 274.7)
-
Step 200
200
#D1D7F6
oklch(88.4% 0.043 276.8)
-
Step 300
300
#B2BDF2
oklch(80.8% 0.076 275.5)
-
Step 400
400
#8C99EC
oklch(70.7% 0.122 276)
-
Step 500
500
#717EE6
oklch(63.2% 0.155 275.7)
-
Step 600
600 (this color)
#646FE0
oklch(59% 0.17 275.7)
-
Step 700
700
#4B53B8
oklch(49.2% 0.157 275.6)
-
Step 800
800
#3D4495
oklch(42.7% 0.131 275.6)
-
Step 900
900
#343A77
oklch(37.7% 0.103 276.1)
-
Step 950
950
#1E2345
oklch(27.1% 0.063 275.1)
#646FE0 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) | #347FE4 | 0.056 |
| Deuteranopia (no green cones) | #1F75DE | 0.062 |
| Tritanopia (no blue cones) | #20889D | 0.149 |
| Achromatopsia (no color) | #7A7A7A | 0.170 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646FE0
#646FE0
oklch(59% 0.17 275.7)
- #937C00
#937C00
oklch(59% 0.121 96)
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 #646FE0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Medium Slate Blue #7B68EE ΔE 0.042
- Cornflower #6A79F7 ΔE 0.042
- Dark Periwinkle #665FD1 ΔE 0.043
- Royal Blue #4169E1 ΔE 0.046
- Light Indigo #6D5ACF ΔE 0.054
- Slate Blue #6A5ACD ΔE 0.055
- Neon Blue #4361EE ΔE 0.060
- Soft Blue #6488EA ΔE 0.063
Use #646FE0 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.