#366DBB
Closest named color: Mid Blue (#276AB3). oklch(53.7% 0.136 257.5), rgb(54, 109, 187).
Aa
White text reads best on this color (5.17:1).
About this color
#366DBB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 54%, its chroma 0.136 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.020 away. White text reads best on it, at 5.17:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | moderately saturated (0.136) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 4.06:1 |
| White text | 5.17:1 |
Values
| HEX | #366DBB |
| RGB | rgb(54, 109, 187) |
| HSL | hsl(215, 55%, 47%) |
| OKLCH | oklch(53.7% 0.136 257.5) |
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 #366DBB | 5.17:1 | AA | Lc -80.7 | Fine for body text |
| Black text on #366DBB | 4.06:1 | AA large text | Lc 28.8 | Dividers and decoration only |
| #366DBB text on white | 5.17:1 | AA | Lc 75.3 | Fine for body text |
| #366DBB text on black | 4.06:1 | AA large text | Lc -26.4 | 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 600.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EBF6
oklch(93.7% 0.017 256.3)
-
Step 200
200
#CBDAF0
oklch(88.4% 0.034 257.9)
-
Step 300
300
#A8C3E8
oklch(81% 0.06 256.3)
-
Step 400
400
#7AA2DD
oklch(70.6% 0.098 258)
-
Step 500
500
#578AD4
oklch(63.1% 0.125 257.7)
-
Step 600
600 (this color)
#366DBB
oklch(53.7% 0.136 257.5)
-
Step 700
700
#2E60A7
oklch(49.2% 0.126 257.6)
-
Step 800
800
#274E87
oklch(42.6% 0.105 258)
-
Step 900
900
#24426C
oklch(37.8% 0.081 257.1)
-
Step 950
950
#16273F
oklch(27.1% 0.05 257.1)
#366DBB 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) | #4874BE | 0.028 |
| Deuteranopia (no green cones) | #3267B9 | 0.017 |
| Tritanopia (no blue cones) | #007F8B | 0.106 |
| Achromatopsia (no color) | #6D6D6D | 0.136 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #366DBB
#366DBB
oklch(53.7% 0.136 257.5)
- #916400
#916400
oklch(53.7% 0.112 77.9)
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 #366DBB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.020
- French Blue #436BAD ΔE 0.024
- Windows Blue #3778BF ΔE 0.031
- Flat Blue #3C73A8 ΔE 0.038
- Nice Blue #107AB0 ΔE 0.046
- Muted Blue #3B719F ΔE 0.048
- Ocean Blue #03719C ΔE 0.060
- Dull Blue #49759C ΔE 0.061
Use #366DBB 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.