#313E78
Closest named color: Twilight Blue (#0A437A). oklch(38.4% 0.1 271.5), rgb(49, 62, 120).
Aa
White text reads best on this color (10.04:1).
About this color
#313E78 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.100 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.035 away. White text reads best on it, at 10.04:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.100) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.09:1 |
| White text | 10.04:1 |
Values
| HEX | #313E78 |
| RGB | rgb(49, 62, 120) |
| HSL | hsl(229, 42%, 33%) |
| OKLCH | oklch(38.4% 0.1 271.5) |
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 #313E78 | 10.04:1 | AAA | Lc -97.3 | Preferred for body text |
| Black text on #313E78 | 2.09:1 | Fails | Lc 10.8 | Not readable |
| #313E78 text on white | 10.04:1 | AAA | Lc 93.1 | Preferred for body text |
| #313E78 text on black | 2.09:1 | Fails | Lc -9.4 | 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
#E4E9F9
oklch(93.5% 0.022 272.1)
-
Step 200
200
#CFD8F5
oklch(88.4% 0.041 271.9)
-
Step 300
300
#AFBFF2
oklch(81% 0.074 271.1)
-
Step 400
400
#869BEB
oklch(70.6% 0.12 271.8)
-
Step 500
500
#6981E5
oklch(63.2% 0.152 271.3)
-
Step 600
600
#5268D3
oklch(55.7% 0.166 271.3)
-
Step 700
700
#4356B7
oklch(49.2% 0.154 271.3)
-
Step 800
800
#374794
oklch(42.8% 0.127 271.2)
-
Step 900
900 (this color)
#313E78
oklch(38.4% 0.1 271.5)
-
Step 950
950
#1C2445
oklch(27.1% 0.062 271.5)
#313E78 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) | #23457A | 0.024 |
| Deuteranopia (no green cones) | #193F77 | 0.027 |
| Tritanopia (no blue cones) | #044B55 | 0.089 |
| Achromatopsia (no color) | #424242 | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313E78
#313E78
oklch(38.4% 0.1 271.5)
- #534100
#534100
oklch(38.4% 0.078 90.9)
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 #313E78, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.035
- Cobalt #1E488F ΔE 0.046
- Dark Slate Blue #483D8B ΔE 0.048
- Light Navy #155084 ΔE 0.055
- Marine Blue #01386A ΔE 0.056
- Blueberry #464196 ΔE 0.060
- Dark Grey Blue #29465B ΔE 0.062
- Dusk Blue #26538D ΔE 0.064
Use #313E78 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.