#366DCA
Closest named color: Windows Blue (#3778BF). oklch(54.7% 0.156 260.2), rgb(54, 109, 202).
Aa
White text reads best on this color (5.00:1).
About this color
#366DCA is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.156 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.037 away. White text reads best on it, at 5.00:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.156) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.19:1 |
| White text | 5.00:1 |
Values
| HEX | #366DCA |
| RGB | rgb(54, 109, 202) |
| HSL | hsl(218, 58%, 50%) |
| OKLCH | oklch(54.7% 0.156 260.2) |
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 #366DCA | 5.00:1 | AA | Lc -79.6 | Fine for body text |
| Black text on #366DCA | 4.19:1 | AA large text | Lc 29.9 | Dividers and decoration only |
| #366DCA text on white | 5.00:1 | AA | Lc 74.2 | Content text, not long reading |
| #366DCA text on black | 4.19:1 | AA large text | Lc -27.5 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E2EAF8
oklch(93.5% 0.021 261.8)
-
Step 200
200
#CBDAF4
oklch(88.5% 0.039 261.5)
-
Step 300
300
#A7C2EF
oklch(81% 0.07 260.6)
-
Step 400
400
#77A1E6
oklch(70.7% 0.112 260)
-
Step 500
500
#5488DF
oklch(63.1% 0.143 260.1)
-
Step 600
600 (this color)
#366DCA
oklch(54.7% 0.156 260.2)
-
Step 700
700
#2B5DB1
oklch(49.1% 0.144 260.2)
-
Step 800
800
#254C90
oklch(42.7% 0.121 260.6)
-
Step 900
900
#224073
oklch(37.7% 0.095 260.3)
-
Step 950
950
#152643
oklch(27% 0.059 260.5)
#366DCA 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) | #3C77CD | 0.028 |
| Deuteranopia (no green cones) | #1A69C8 | 0.023 |
| Tritanopia (no blue cones) | #008392 | 0.122 |
| Achromatopsia (no color) | #6F6F6F | 0.156 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #366DCA
#366DCA
oklch(54.7% 0.156 260.2)
- #936800
#936800
oklch(54.8% 0.113 80.1)
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 #366DCA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.037
- Mid Blue #276AB3 ΔE 0.039
- Royal Blue #4169E1 ΔE 0.039
- French Blue #436BAD ΔE 0.045
- Cerulean Blue #056EEE ΔE 0.058
- Flat Blue #3C73A8 ΔE 0.059
- Nice Blue #107AB0 ΔE 0.062
- Warm Blue #4B57DB ΔE 0.063
Use #366DCA 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.