#333C71
Closest named color: Twilight Blue (#0A437A). oklch(37.6% 0.091 274), rgb(51, 60, 113).
Aa
White text reads best on this color (10.36:1).
About this color
#333C71 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.091 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.041 away. White text reads best on it, at 10.36:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.091) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.02:1 |
| White text | 10.36:1 |
Values
| HEX | #333C71 |
| RGB | rgb(51, 60, 113) |
| HSL | hsl(231, 38%, 32%) |
| OKLCH | oklch(37.6% 0.091 274) |
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 #333C71 | 10.36:1 | AAA | Lc -98.0 | Preferred for body text |
| Black text on #333C71 | 2.02:1 | Fails | Lc 10.0 | Not readable |
| #333C71 text on white | 10.36:1 | AAA | Lc 93.9 | Preferred for body text |
| #333C71 text on black | 2.02:1 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E5E9F7
oklch(93.5% 0.019 273.2)
-
Step 200
200
#D1D8F3
oklch(88.5% 0.038 274.1)
-
Step 300
300
#B2BEED
oklch(80.8% 0.068 273.6)
-
Step 400
400
#8B9BE5
oklch(70.6% 0.11 273.9)
-
Step 500
500
#7081DD
oklch(63.2% 0.139 273.9)
-
Step 600
600
#5968CA
oklch(55.5% 0.151 273.9)
-
Step 700
700
#4A56AF
oklch(49.1% 0.141 274.2)
-
Step 800
800
#3C478E
oklch(42.7% 0.117 273.8)
-
Step 900
900 (this color)
#333C71
oklch(37.6% 0.091 274)
-
Step 950
950
#1E2442
oklch(27.1% 0.056 273.5)
#333C71 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) | #254373 | 0.025 |
| Deuteranopia (no green cones) | #1F3E70 | 0.025 |
| Tritanopia (no blue cones) | #174751 | 0.079 |
| Achromatopsia (no color) | #404040 | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #333C71
#333C71
oklch(37.6% 0.091 274)
- #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 #333C71, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.041
- Marine Blue #01386A ΔE 0.053
- Dark Slate Blue #483D8B ΔE 0.056
- Dark Grey Blue #29465B ΔE 0.056
- Cobalt #1E488F ΔE 0.058
- Prussian Blue #1D3557 ΔE 0.058
- Light Navy #155084 ΔE 0.063
- Charcoal #264653 ΔE 0.069
Use #333C71 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.