#313C80
Closest named color: Twilight Blue (#0A437A). oklch(38.6% 0.115 273), rgb(49, 60, 128).
Aa
White text reads best on this color (10.05:1).
About this color
#313C80 is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.115 and its hue 273°. 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 10.05:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.115) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.08:1 |
| White text | 10.05:1 |
Values
| HEX | #313C80 |
| RGB | rgb(49, 60, 128) |
| HSL | hsl(232, 45%, 35%) |
| OKLCH | oklch(38.6% 0.115 273) |
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 #313C80 | 10.05:1 | AAA | Lc -97.2 | Preferred for body text |
| Black text on #313C80 | 2.08:1 | Fails | Lc 10.9 | Not readable |
| #313C80 text on white | 10.05:1 | AAA | Lc 93.1 | Preferred for body text |
| #313C80 text on black | 2.08:1 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E4E9FB
oklch(93.6% 0.025 273.5)
-
Step 200
200
#CED8FA
oklch(88.5% 0.048 272.4)
-
Step 300
300
#AEBDF9
oklch(80.8% 0.087 273.5)
-
Step 400
400
#8599F6
oklch(70.7% 0.138 273.2)
-
Step 500
500
#687DF2
oklch(63.1% 0.175 272.7)
-
Step 600
600
#5262E1
oklch(55.5% 0.192 273)
-
Step 700
700
#4351C3
oklch(49.2% 0.177 272.8)
-
Step 800
800
#37439E
oklch(42.8% 0.147 272.9)
-
Step 900
900 (this color)
#313C80
oklch(38.6% 0.115 273)
-
Step 950
950
#1B2249
oklch(26.9% 0.072 272.9)
#313C80 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) | #164682 | 0.035 |
| Deuteranopia (no green cones) | #033F7F | 0.039 |
| Tritanopia (no blue cones) | #004C58 | 0.100 |
| Achromatopsia (no color) | #424242 | 0.115 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313C80
#313C80
oklch(38.6% 0.115 273)
- #524200
#524200
oklch(38.5% 0.079 93.2)
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 #313C80, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.040
- Cobalt #1E488F ΔE 0.041
- Dark Slate Blue #483D8B ΔE 0.041
- Blueberry #464196 ΔE 0.051
- Light Navy #155084 ΔE 0.058
- Marine Blue #01386A ΔE 0.062
- Dusk Blue #26538D ΔE 0.065
- Deep Sea Blue #015482 ΔE 0.072
Use #313C80 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.