#6366B9
Closest named color: Iris (#6258C4). oklch(54.7% 0.127 279.7), rgb(99, 102, 185).
Aa
White text reads best on this color (5.08:1).
About this color
#6366B9 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.127 and its hue 280°. Its hue sits on the cool side of the wheel. The nearest named color is Iris (#6258C4), ΔE 0.042 away. White text reads best on it, at 5.08:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.127) |
| Temperature | cool |
| Nearest name | Iris (#6258C4) |
| Black text | 4.13:1 |
| White text | 5.08:1 |
Values
| HEX | #6366B9 |
| RGB | rgb(99, 102, 185) |
| HSL | hsl(238, 38%, 56%) |
| OKLCH | oklch(54.7% 0.127 279.7) |
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 #6366B9 | 5.08:1 | AA | Lc -80.3 | Fine for body text |
| Black text on #6366B9 | 4.13:1 | AA large text | Lc 29.1 | Dividers and decoration only |
| #6366B9 text on white | 5.08:1 | AA | Lc 74.9 | Content text, not long reading |
| #6366B9 text on black | 4.13:1 | AA large text | Lc -26.8 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E7E9F5
oklch(93.6% 0.016 278.5)
-
Step 200
200
#D4D7EE
oklch(88.4% 0.032 279.8)
-
Step 300
300
#B8BDE6
oklch(80.8% 0.058 279.6)
-
Step 400
400
#959AD9
oklch(70.6% 0.092 280.3)
-
Step 500
500
#7C81CF
oklch(63.2% 0.117 279.7)
-
Step 600
600 (this color)
#6366B9
oklch(54.7% 0.127 279.7)
-
Step 700
700
#5457A2
oklch(49.1% 0.118 279.4)
-
Step 800
800
#454783
oklch(42.6% 0.098 279.9)
-
Step 900
900
#3A3C69
oklch(37.7% 0.076 280.1)
-
Step 950
950
#22233E
oklch(26.9% 0.05 280.9)
#6366B9 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) | #4572BC | 0.045 |
| Deuteranopia (no green cones) | #3F6BB7 | 0.045 |
| Tritanopia (no blue cones) | #457786 | 0.111 |
| Achromatopsia (no color) | #6E6E6E | 0.128 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #6366B9
#6366B9
oklch(54.7% 0.127 279.7)
- #817100
#817100
oklch(54.7% 0.113 99.4)
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 #6366B9, closest first.
No curated palette has a color within ΔE 0.04 of #6366B9.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Iris #6258C4 ΔE 0.042
- Dark Periwinkle #665FD1 ΔE 0.043
- Slate Blue #6A5ACD ΔE 0.046
- French Blue #436BAD ΔE 0.047
- Light Indigo #6D5ACF ΔE 0.049
- Windows Blue #3778BF ΔE 0.062
- Flat Blue #3C73A8 ΔE 0.065
- Mid Blue #276AB3 ΔE 0.065
Use #6366B9 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.