#313A73
Closest named color: Twilight Blue (#0A437A). oklch(37.2% 0.097 274), rgb(49, 58, 115).
Aa
White text reads best on this color (10.58:1).
About this color
#313A73 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.097 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.040 away. White text reads best on it, at 10.58:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.98:1 |
| White text | 10.58:1 |
Values
| HEX | #313A73 |
| RGB | rgb(49, 58, 115) |
| HSL | hsl(232, 40%, 32%) |
| OKLCH | oklch(37.2% 0.097 274) |
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 #313A73 | 10.58:1 | AAA | Lc -98.4 | Preferred for body text |
| Black text on #313A73 | 1.98:1 | Fails | Lc 9.5 | Not readable |
| #313A73 text on white | 10.58:1 | AAA | Lc 94.4 | Preferred for body text |
| #313A73 text on black | 1.98:1 | Fails | Lc -8.2 | Not readable |
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 900.
-
Step 50
50
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E5E9F8
oklch(93.5% 0.021 274)
-
Step 200
200
#D0D8F5
oklch(88.5% 0.041 273.3)
-
Step 300
300
#B1BEF1
oklch(80.9% 0.074 273.5)
-
Step 400
400
#8A9BE9
oklch(70.8% 0.116 273.7)
-
Step 500
500
#6E80E3
oklch(63.2% 0.149 273.6)
-
Step 600
600
#5867D1
oklch(55.7% 0.163 273.9)
-
Step 700
700
#4855B5
oklch(49.2% 0.151 273.7)
-
Step 800
800
#3B4692
oklch(42.7% 0.125 273.7)
-
Step 900
900 (this color)
#313A73
oklch(37.2% 0.097 274)
-
Step 950
950
#1D2344
oklch(26.9% 0.062 273.8)
#313A73 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) | #204275 | 0.028 |
| Deuteranopia (no green cones) | #173C72 | 0.030 |
| Tritanopia (no blue cones) | #0F4751 | 0.086 |
| Achromatopsia (no color) | #3F3F3F | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313A73
#313A73
oklch(37.2% 0.097 274)
- #4E3F00
#4E3F00
oklch(37.3% 0.076 93.6)
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 #313A73, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.040
- Marine Blue #01386A ΔE 0.050
- Dark Slate Blue #483D8B ΔE 0.056
- Cobalt #1E488F ΔE 0.058
- Prussian Blue #1D3557 ΔE 0.058
- Dark Grey Blue #29465B ΔE 0.062
- Light Navy #155084 ΔE 0.066
- Blueberry #464196 ΔE 0.070
Use #313A73 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.