#333573
Closest named color: Twilight Blue (#0A437A). oklch(36.3% 0.104 278.4), rgb(51, 53, 115).
Aa
White text reads best on this color (11.06:1).
About this color
#333573 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.104 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.051 away. White text reads best on it, at 11.06:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.104) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.89:1 |
| White text | 11.06:1 |
Values
| HEX | #333573 |
| RGB | rgb(51, 53, 115) |
| HSL | hsl(238, 39%, 33%) |
| OKLCH | oklch(36.3% 0.104 278.4) |
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 #333573 | 11.06:1 | AAA | Lc -99.2 | Preferred for body text |
| Black text on #333573 | 1.89:1 | Fails | Lc 8.5 | Not readable |
| #333573 text on white | 11.06:1 | AAA | Lc 95.4 | Preferred for body text |
| #333573 text on black | 1.89:1 | Fails | Lc 0.0 | 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
#F4F5FD
oklch(97.2% 0.011 280.5)
-
Step 100
100
#E6E9F9
oklch(93.6% 0.022 277.5)
-
Step 200
200
#D2D7F6
oklch(88.5% 0.043 278.2)
-
Step 300
300
#B5BCF3
oklch(80.9% 0.078 278.9)
-
Step 400
400
#8F98ED
oklch(70.7% 0.124 278.1)
-
Step 500
500
#767BE8
oklch(63.1% 0.161 278.7)
-
Step 600
600
#6062D6
oklch(55.6% 0.174 278.4)
-
Step 700
700
#5050B9
oklch(49.1% 0.162 278.6)
-
Step 800
800
#414296
oklch(42.6% 0.135 278.5)
-
Step 900
900 (this color)
#333573
oklch(36.3% 0.104 278.4)
-
Step 950
950
#202246
oklch(27.1% 0.066 278.6)
#333573 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) | #153E75 | 0.039 |
| Deuteranopia (no green cones) | #0C3972 | 0.042 |
| Tritanopia (no blue cones) | #16434E | 0.092 |
| Achromatopsia (no color) | #3C3C3C | 0.105 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #333573
#333573
oklch(36.3% 0.104 278.4)
- #483E00
#483E00
oklch(36.3% 0.075 99)
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 #333573, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.051
- Marine Blue #01386A ΔE 0.052
- Dark Slate Blue #483D8B ΔE 0.058
- Prussian Blue #1D3557 ΔE 0.059
- Cobalt #1E488F ΔE 0.067
- Marine #042E60 ΔE 0.068
- Blueberry #464196 ΔE 0.073
- Dark Grey Blue #29465B ΔE 0.073
Use #333573 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.