#313C6B
Closest named color: Twilight Blue (#0A437A). oklch(37.1% 0.082 271.9), rgb(49, 60, 107).
Aa
White text reads best on this color (10.55:1).
About this color
#313C6B is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.082 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.042 away. White text reads best on it, at 10.55:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.082) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.98:1 |
| White text | 10.55:1 |
Values
| HEX | #313C6B |
| RGB | rgb(49, 60, 107) |
| HSL | hsl(229, 37%, 31%) |
| OKLCH | oklch(37.1% 0.082 271.9) |
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 #313C6B | 10.55:1 | AAA | Lc -98.3 | Preferred for body text |
| Black text on #313C6B | 1.98:1 | Fails | Lc 9.5 | Not readable |
| #313C6B text on white | 10.55:1 | AAA | Lc 94.4 | Preferred for body text |
| #313C6B 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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5E9F6
oklch(93.5% 0.018 272.3)
-
Step 200
200
#D1D8F0
oklch(88.4% 0.034 272.8)
-
Step 300
300
#B2BFE9
oklch(80.9% 0.061 271.5)
-
Step 400
400
#8B9DDE
oklch(70.7% 0.098 271.8)
-
Step 500
500
#6F83D5
oklch(63% 0.126 272)
-
Step 600
600
#586BC2
oklch(55.5% 0.136 272)
-
Step 700
700
#4859A8
oklch(49.1% 0.127 271.8)
-
Step 800
800
#3B4988
oklch(42.6% 0.105 271.8)
-
Step 900
900 (this color)
#313C6B
oklch(37.1% 0.082 271.9)
-
Step 950
950
#1E2440
oklch(27% 0.053 273.2)
#313C6B 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) | #29416D | 0.017 |
| Deuteranopia (no green cones) | #233D6A | 0.018 |
| Tritanopia (no blue cones) | #17464E | 0.073 |
| Achromatopsia (no color) | #3F3F3F | 0.082 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313C6B
#313C6B
oklch(37.1% 0.082 271.9)
- #4E3E00
#4E3E00
oklch(37% 0.076 92.3)
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 #313C6B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.042
- Dark Grey Blue #29465B ΔE 0.048
- Marine Blue #01386A ΔE 0.048
- Prussian Blue #1D3557 ΔE 0.049
- Dark Blue Grey #1F3B4D ΔE 0.060
- Charcoal #264653 ΔE 0.060
- Cobalt #1E488F ΔE 0.066
- Dark Slate Blue #483D8B ΔE 0.066
Use #313C6B 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.