#31377A
Closest named color: Twilight Blue (#0A437A). oklch(37.1% 0.113 275.6), rgb(49, 55, 122).
Aa
White text reads best on this color (10.72:1).
About this color
#31377A is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.113 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.045 away. White text reads best on it, at 10.72:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.95:1 |
| White text | 10.72:1 |
Values
| HEX | #31377A |
| RGB | rgb(49, 55, 122) |
| HSL | hsl(235, 43%, 34%) |
| OKLCH | oklch(37.1% 0.113 275.6) |
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 #31377A | 10.72:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #31377A | 1.95:1 | Fails | Lc 9.3 | Not readable |
| #31377A text on white | 10.72:1 | AAA | Lc 94.6 | Preferred for body text |
| #31377A text on black | 1.95:1 | Fails | Lc -8.0 | 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
#E5E9FB
oklch(93.6% 0.025 275.9)
-
Step 200
200
#D0D7F9
oklch(88.5% 0.047 276.2)
-
Step 300
300
#B1BDF8
oklch(81% 0.085 275.4)
-
Step 400
400
#8A98F4
oklch(70.7% 0.135 275.8)
-
Step 500
500
#6F7BF0
oklch(63.1% 0.174 275.8)
-
Step 600
600
#5961DE
oklch(55.6% 0.188 275.7)
-
Step 700
700
#494FC1
oklch(49% 0.175 275.6)
-
Step 800
800
#3C429C
oklch(42.7% 0.144 275.6)
-
Step 900
900 (this color)
#31377A
oklch(37.1% 0.113 275.6)
-
Step 950
950
#1D2249
oklch(27% 0.072 275)
#31377A 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) | #10417C | 0.039 |
| Deuteranopia (no green cones) | #003B79 | 0.043 |
| Tritanopia (no blue cones) | #034653 | 0.098 |
| Achromatopsia (no color) | #3E3E3E | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #31377A
#31377A
oklch(37.1% 0.113 275.6)
- #4C3F00
#4C3F00
oklch(37% 0.076 95.8)
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 #31377A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.045
- Dark Slate Blue #483D8B ΔE 0.050
- Marine Blue #01386A ΔE 0.054
- Cobalt #1E488F ΔE 0.056
- Blueberry #464196 ΔE 0.063
- Prussian Blue #1D3557 ΔE 0.068
- Light Navy #155084 ΔE 0.072
- Marine #042E60 ΔE 0.074
Use #31377A 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.