#646FAE
Closest named color: French Blue (#436BAD). oklch(56% 0.099 275.2), rgb(100, 111, 174).
Aa
White text reads best on this color (4.74:1).
About this color
#646FAE is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.099 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.044 away. White text reads best on it, at 4.74:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 4.42:1 |
| White text | 4.74:1 |
Values
| HEX | #646FAE |
| RGB | rgb(100, 111, 174) |
| HSL | hsl(231, 31%, 54%) |
| OKLCH | oklch(56% 0.099 275.2) |
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 #646FAE | 4.74:1 | AA | Lc -78.3 | Fine for body text |
| Black text on #646FAE | 4.42:1 | AA large text | Lc 31.2 | Non-text elements, placeholder text |
| #646FAE text on white | 4.74:1 | AA | Lc 72.9 | Content text, not long reading |
| #646FAE text on black | 4.42:1 | AA large text | Lc -28.8 | 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
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E7E9F3
oklch(93.5% 0.014 277.1)
-
Step 200
200
#D4D8EA
oklch(88.5% 0.025 275.9)
-
Step 300
300
#B8BFDE
oklch(80.9% 0.044 275.3)
-
Step 400
400
#939ECD
oklch(70.8% 0.07 274.3)
-
Step 500
500
#7A85C0
oklch(63.1% 0.09 275.4)
-
Step 600
600 (this color)
#646FAE
oklch(56% 0.099 275.2)
-
Step 700
700
#525C94
oklch(49.2% 0.09 274.9)
-
Step 800
800
#434B78
oklch(42.7% 0.075 275.1)
-
Step 900
900
#383F61
oklch(37.7% 0.059 274.4)
-
Step 950
950
#212539
oklch(27% 0.038 274.9)
#646FAE 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) | #5976B1 | 0.022 |
| Deuteranopia (no green cones) | #5370AD | 0.022 |
| Tritanopia (no blue cones) | #4C7C86 | 0.088 |
| Achromatopsia (no color) | #737373 | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646FAE
#646FAE
oklch(56% 0.099 275.2)
- #867325
#867325
oklch(55.8% 0.098 95.1)
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 #646FAE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.044
- Flat Blue #3C73A8 ΔE 0.048
- Dull Blue #49759C ΔE 0.050
- Windows Blue #3778BF ΔE 0.053
- Stormy Blue #507B9C ΔE 0.055
- Muted Blue #3B719F ΔE 0.055
- Steel Blue #4682B4 ΔE 0.058
- Dark Lavender #856798 ΔE 0.059
Use #646FAE 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.