#366D99
Closest named color: Muted Blue (#3B719F). oklch(51.7% 0.091 245), rgb(54, 109, 153).
Aa
White text reads best on this color (5.52:1).
About this color
#366D99 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 52%, its chroma 0.091 and its hue 245°. Its hue sits on the cool side of the wheel. The nearest named color is Muted Blue (#3B719F), ΔE 0.015 away. White text reads best on it, at 5.52:1.
| Hue family | Blues |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.091) |
| Temperature | cool |
| Nearest name | Muted Blue (#3B719F) |
| Black text | 3.80:1 |
| White text | 5.52:1 |
Values
| HEX | #366D99 |
| RGB | rgb(54, 109, 153) |
| HSL | hsl(207, 48%, 41%) |
| OKLCH | oklch(51.7% 0.091 245) |
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 #366D99 | 5.52:1 | AA | Lc -82.7 | Fine for body text |
| Black text on #366D99 | 3.80:1 | AA large text | Lc 26.7 | Dividers and decoration only |
| #366D99 text on white | 5.52:1 | AA | Lc 77.4 | Fine for body text |
| #366D99 text on black | 3.80:1 | AA large text | Lc -24.4 | 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF2
oklch(93.6% 0.013 244.3)
-
Step 200
200
#CCDBE9
oklch(88.4% 0.025 246.2)
-
Step 300
300
#AAC4DC
oklch(80.9% 0.044 246.2)
-
Step 400
400
#7BA6CA
oklch(70.7% 0.07 244.3)
-
Step 500
500
#588FBD
oklch(63.1% 0.091 245.2)
-
Step 600
600
#3C79A9
oklch(55.7% 0.098 244.7)
-
Step 700
700 (this color)
#366D99
oklch(51.7% 0.091 245)
-
Step 800
800
#275375
oklch(42.7% 0.075 244.2)
-
Step 900
900
#25455F
oklch(37.8% 0.059 244.8)
-
Step 950
950
#162837
oklch(26.9% 0.037 244.9)
#366D99 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) | #5A6E9B | 0.041 |
| Deuteranopia (no green cones) | #4C6498 | 0.032 |
| Tritanopia (no blue cones) | #00787C | 0.070 |
| Achromatopsia (no color) | #696969 | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #366D99
#366D99
oklch(51.7% 0.091 245)
- #8C5C29
#8C5C29
oklch(51.7% 0.091 64.8)
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 #366D99, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Muted Blue #3B719F ΔE 0.015
- Ocean Blue #03719C ΔE 0.025
- Flat Blue #3C73A8 ΔE 0.028
- Denim #3B638C ΔE 0.032
- Sea Blue #047495 ΔE 0.032
- Dull Blue #49759C ΔE 0.032
- Peacock Blue #016795 ΔE 0.036
- French Blue #436BAD ΔE 0.037
Use #366D99 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.