#3866A5
Closest named color: French Blue (#436BAD). oklch(50.9% 0.113 256.7), rgb(56, 102, 165).
Aa
White text reads best on this color (5.81:1).
About this color
#3866A5 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.113 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.022 away. White text reads best on it, at 5.81:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 3.61:1 |
| White text | 5.81:1 |
Values
| HEX | #3866A5 |
| RGB | rgb(56, 102, 165) |
| HSL | hsl(215, 49%, 43%) |
| OKLCH | oklch(50.9% 0.113 256.7) |
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 #3866A5 | 5.81:1 | AA | Lc -84.1 | Fine for body text |
| Black text on #3866A5 | 3.61:1 | AA large text | Lc 25.2 | Dividers and decoration only |
| #3866A5 text on white | 5.81:1 | AA | Lc 78.9 | Fine for body text |
| #3866A5 text on black | 3.61:1 | AA large text | Lc -22.9 | 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 700.
-
Step 50
50
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E3EAF5
oklch(93.5% 0.017 259.4)
-
Step 200
200
#CDDAEE
oklch(88.5% 0.031 258.9)
-
Step 300
300
#AAC3E4
oklch(81% 0.054 255.4)
-
Step 400
400
#7DA3D7
oklch(70.8% 0.087 256.4)
-
Step 500
500
#5C8BCC
oklch(63.1% 0.111 256.7)
-
Step 600
600
#4174B9
oklch(55.6% 0.121 256.5)
-
Step 700
700 (this color)
#3866A5
oklch(50.9% 0.113 256.7)
-
Step 800
800
#2B4F81
oklch(42.6% 0.093 257)
-
Step 900
900
#274268
oklch(37.7% 0.073 257.1)
-
Step 950
950
#17273D
oklch(27% 0.047 256.6)
#3866A5 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) | #4A6BA8 | 0.026 |
| Deuteranopia (no green cones) | #3B61A4 | 0.014 |
| Tritanopia (no blue cones) | #00747D | 0.091 |
| Achromatopsia (no color) | #656565 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3866A5
#3866A5
oklch(50.9% 0.113 256.7)
- #875C00
#875C00
oklch(50.8% 0.106 77.1)
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 #3866A5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.022
- Mid Blue #276AB3 ΔE 0.025
- Dusky Blue #475F94 ΔE 0.032
- Muted Blue #3B719F ΔE 0.036
- Flat Blue #3C73A8 ΔE 0.038
- Denim Blue #3B5B92 ΔE 0.039
- Denim #3B638C ΔE 0.039
- Peacock Blue #016795 ΔE 0.042
Use #3866A5 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.