#646AE0
Closest named color: Dark Periwinkle (#665FD1). oklch(58.1% 0.176 277.2), rgb(100, 106, 224).
Aa
Black text reads best on this color (4.67:1).
About this color
#646AE0 is a medium-dark, vivid blue. In OKLCH its lightness is 58%, its chroma 0.176 and its hue 277°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.033 away. Black text reads best on it, at 4.67:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | vivid (0.176) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 4.67:1 |
| White text | 4.48:1 |
Values
| HEX | #646AE0 |
| RGB | rgb(100, 106, 224) |
| HSL | hsl(237, 67%, 64%) |
| OKLCH | oklch(58.1% 0.176 277.2) |
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 #646AE0 | 4.48:1 | AA large text | Lc -76.3 | Fine for body text |
| Black text on #646AE0 | 4.67:1 | AA | Lc 33.2 | Non-text elements, placeholder text |
| #646AE0 text on white | 4.48:1 | AA large text | Lc 70.9 | Content text, not long reading |
| #646AE0 text on black | 4.67:1 | AA | Lc -30.8 | 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
#E6E9FA
oklch(93.7% 0.023 277.9)
-
Step 200
200
#D1D7F7
oklch(88.5% 0.044 277.1)
-
Step 300
300
#B3BCF4
oklch(80.8% 0.08 277.4)
-
Step 400
400
#8D98EF
oklch(70.7% 0.127 277.1)
-
Step 500
500
#737CE9
oklch(63.1% 0.162 277.1)
-
Step 600
600 (this color)
#646AE0
oklch(58.1% 0.176 277.2)
-
Step 700
700
#4D50BB
oklch(49% 0.165 277.2)
-
Step 800
800
#3F4397
oklch(42.8% 0.135 277)
-
Step 900
900
#353978
oklch(37.6% 0.106 277.3)
-
Step 950
950
#1F2246
oklch(27% 0.066 277.4)
#646AE0 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) | #257CE4 | 0.067 |
| Deuteranopia (no green cones) | #0372DE | 0.072 |
| Tritanopia (no blue cones) | #22859B | 0.154 |
| Achromatopsia (no color) | #777777 | 0.177 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646AE0
#646AE0
oklch(58.1% 0.176 277.2)
- #8F7A00
#8F7A00
oklch(58.2% 0.12 97)
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 #646AE0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.033
- Medium Slate Blue #7B68EE ΔE 0.040
- Royal Blue #4169E1 ΔE 0.042
- Light Indigo #6D5ACF ΔE 0.044
- Slate Blue #6A5ACD ΔE 0.045
- Cornflower #6A79F7 ΔE 0.049
- Neon Blue #4361EE ΔE 0.053
- Iris #6258C4 ΔE 0.059
Use #646AE0 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.