#31397D
Closest named color: Twilight Blue (#0A437A). oklch(37.7% 0.114 274.5), rgb(49, 57, 125).
Aa
White text reads best on this color (10.43:1).
About this color
#31397D is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.114 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.043 away. White text reads best on it, at 10.43:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.114) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.01:1 |
| White text | 10.43:1 |
Values
| HEX | #31397D |
| RGB | rgb(49, 57, 125) |
| HSL | hsl(234, 44%, 34%) |
| OKLCH | oklch(37.7% 0.114 274.5) |
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 #31397D | 10.43:1 | AAA | Lc -98.0 | Preferred for body text |
| Black text on #31397D | 2.01:1 | Fails | Lc 10.0 | Not readable |
| #31397D text on white | 10.43:1 | AAA | Lc 94.0 | Preferred for body text |
| #31397D text on black | 2.01:1 | Fails | Lc -8.6 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E4E9FB
oklch(93.6% 0.025 273.5)
-
Step 200
200
#CFD7F9
oklch(88.4% 0.048 274.9)
-
Step 300
300
#B0BDF9
oklch(81% 0.086 274.8)
-
Step 400
400
#8798F5
oklch(70.6% 0.137 274.5)
-
Step 500
500
#6C7CF1
oklch(63.1% 0.174 274.4)
-
Step 600
600
#5661E0
oklch(55.5% 0.191 274.6)
-
Step 700
700
#4750C3
oklch(49.2% 0.177 274.5)
-
Step 800
800
#3A429D
oklch(42.7% 0.146 274.6)
-
Step 900
900 (this color)
#31397D
oklch(37.7% 0.114 274.5)
-
Step 950
950
#1C2249
oklch(27% 0.072 274)
#31397D 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) | #11437F | 0.038 |
| Deuteranopia (no green cones) | #003C7C | 0.042 |
| Tritanopia (no blue cones) | #004955 | 0.101 |
| Achromatopsia (no color) | #404040 | 0.114 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #31397D
#31397D
oklch(37.7% 0.114 274.5)
- #4F4000
#4F4000
oklch(37.6% 0.077 93.9)
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 #31397D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.043
- Dark Slate Blue #483D8B ΔE 0.046
- Cobalt #1E488F ΔE 0.049
- Marine Blue #01386A ΔE 0.057
- Blueberry #464196 ΔE 0.057
- Light Navy #155084 ΔE 0.066
- Prussian Blue #1D3557 ΔE 0.073
- Dusk Blue #26538D ΔE 0.074
Use #31397D 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.