#37539B
Closest named color: Dusk Blue (#26538D). oklch(45.9% 0.122 265.8), rgb(55, 83, 155).
Aa
White text reads best on this color (7.30:1).
About this color
#37539B is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.122 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.030 away. White text reads best on it, at 7.30:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.87:1 |
| White text | 7.30:1 |
Values
| HEX | #37539B |
| RGB | rgb(55, 83, 155) |
| HSL | hsl(223, 48%, 41%) |
| OKLCH | oklch(45.9% 0.122 265.8) |
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 #37539B | 7.30:1 | AAA | Lc -90.0 | Preferred for body text |
| Black text on #37539B | 2.87:1 | Fails | Lc 18.9 | Dividers and decoration only |
| #37539B text on white | 7.30:1 | AAA | Lc 85.1 | Fine for body text |
| #37539B text on black | 2.87:1 | Fails | Lc -16.9 | 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 800.
-
Step 50
50
#F2F5FC
oklch(97% 0.01 267.4)
-
Step 100
100
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CDD9F4
oklch(88.5% 0.039 266.5)
-
Step 300
300
#ABC0F0
oklch(80.9% 0.072 266.3)
-
Step 400
400
#7F9EE8
oklch(70.6% 0.114 266.2)
-
Step 500
500
#5F85E1
oklch(63.2% 0.145 265.5)
-
Step 600
600
#476CCF
oklch(55.6% 0.159 266)
-
Step 700
700
#385AB3
oklch(49.1% 0.147 265.6)
-
Step 800
800 (this color)
#37539B
oklch(45.9% 0.122 265.8)
-
Step 900
900
#293E74
oklch(37.6% 0.096 266)
-
Step 950
950
#182544
oklch(27% 0.061 265.4)
#37539B 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) | #305B9E | 0.022 |
| Deuteranopia (no green cones) | #1F529A | 0.023 |
| Tritanopia (no blue cones) | #00636F | 0.102 |
| Achromatopsia (no color) | #565656 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37539B
#37539B
oklch(45.9% 0.122 265.8)
- #6F5300
#6F5300
oklch(45.9% 0.094 85.9)
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 #37539B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.030
- Denim Blue #3B5B92 ΔE 0.030
- Twilight #4E518B ΔE 0.038
- Light Navy Blue #2E5A88 ΔE 0.041
- Dusky Blue #475F94 ΔE 0.045
- Cobalt #1E488F ΔE 0.047
- Blueberry #464196 ΔE 0.049
- Light Navy #155084 ΔE 0.051
Use #37539B 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.