#646FA0
Closest named color: Dull Blue (#49759C). oklch(55.3% 0.078 273.9), rgb(100, 111, 160).
Aa
White text reads best on this color (4.85:1).
About this color
#646FA0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.078 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Dull Blue (#49759C), ΔE 0.037 away. White text reads best on it, at 4.85:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.078) |
| Temperature | cool |
| Nearest name | Dull Blue (#49759C) |
| Black text | 4.32:1 |
| White text | 4.85:1 |
Values
| HEX | #646FA0 |
| RGB | rgb(100, 111, 160) |
| HSL | hsl(229, 24%, 51%) |
| OKLCH | oklch(55.3% 0.078 273.9) |
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 #646FA0 | 4.85:1 | AA | Lc -79.1 | Fine for body text |
| Black text on #646FA0 | 4.32:1 | AA large text | Lc 30.4 | Non-text elements, placeholder text |
| #646FA0 text on white | 4.85:1 | AA | Lc 73.6 | Content text, not long reading |
| #646FA0 text on black | 4.32:1 | AA large text | Lc -28.1 | 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
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E7E9F1
oklch(93.5% 0.011 274.9)
-
Step 200
200
#D5D8E6
oklch(88.4% 0.019 276.3)
-
Step 300
300
#B9C0D8
oklch(81% 0.035 272.7)
-
Step 400
400
#959FC4
oklch(70.7% 0.055 273.1)
-
Step 500
500
#7C87B5
oklch(63.2% 0.071 273.8)
-
Step 600
600 (this color)
#646FA0
oklch(55.3% 0.078 273.9)
-
Step 700
700
#545E8A
oklch(49.2% 0.072 273.7)
-
Step 800
800
#454D70
oklch(42.8% 0.059 273.8)
-
Step 900
900
#3A405B
oklch(37.8% 0.047 274.3)
-
Step 950
950
#222535
oklch(26.9% 0.03 276)
#646FA0 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) | #5F74A2 | 0.014 |
| Deuteranopia (no green cones) | #5B6F9F | 0.012 |
| Tritanopia (no blue cones) | #527980 | 0.071 |
| Achromatopsia (no color) | #717171 | 0.078 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646FA0
#646FA0
oklch(55.3% 0.078 273.9)
- #81723A
#81723A
oklch(55.3% 0.078 94.7)
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 #646FA0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dull Blue #49759C ΔE 0.037
- Stormy Blue #507B9C ΔE 0.042
- Metallic Blue #4F738E ΔE 0.044
- Flat Blue #3C73A8 ΔE 0.046
- Muted Blue #3B719F ΔE 0.048
- French Blue #436BAD ΔE 0.048
- Cerulean #457B9D ΔE 0.049
- Dark Lavender #856798 ΔE 0.053
Use #646FA0 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.