#373563
Closest named color: Prussian Blue (#1D3557). oklch(35.5% 0.078 283.6), rgb(55, 53, 99).
Aa
White text reads best on this color (11.33:1).
About this color
#373563 is a dark, moderately saturated purple. In OKLCH its lightness is 35%, its chroma 0.078 and its hue 284°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.044 away. White text reads best on it, at 11.33:1.
| Hue family | Purples |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.078) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.85:1 |
| White text | 11.33:1 |
Values
| HEX | #373563 |
| RGB | rgb(55, 53, 99) |
| HSL | hsl(243, 30%, 30%) |
| OKLCH | oklch(35.5% 0.078 283.6) |
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 #373563 | 11.33:1 | AAA | Lc -99.8 | Preferred for body text |
| Black text on #373563 | 1.85:1 | Fails | Lc 7.8 | Not readable |
| #373563 text on white | 11.33:1 | AAA | Lc 96.1 | Preferred for body text |
| #373563 text on black | 1.85:1 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E8E9F5
oklch(93.7% 0.016 282.3)
-
Step 200
200
#D6D7EF
oklch(88.6% 0.033 283.8)
-
Step 300
300
#BBBCE6
oklch(80.8% 0.059 283.9)
-
Step 400
400
#9999DA
oklch(70.8% 0.094 283.7)
-
Step 500
500
#817ECF
oklch(63% 0.12 284.1)
-
Step 600
600
#6B66BC
oklch(55.5% 0.131 283.9)
-
Step 700
700
#5955A2
oklch(49.1% 0.12 283.4)
-
Step 800
800
#494684
oklch(42.8% 0.101 283.5)
-
Step 900
900 (this color)
#373563
oklch(35.5% 0.078 283.6)
-
Step 950
950
#23233E
oklch(27% 0.05 282.6)
#373563 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) | #243C65 | 0.031 |
| Deuteranopia (no green cones) | #223962 | 0.031 |
| Tritanopia (no blue cones) | #2A3E47 | 0.067 |
| Achromatopsia (no color) | #3A3A3A | 0.079 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373563
#373563
oklch(35.5% 0.078 283.6)
- #433D00
#433D00
oklch(35.5% 0.075 103.3)
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 #373563, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.044
- Marine Blue #01386A ΔE 0.056
- Dark Blue Grey #1F3B4D ΔE 0.059
- Dark Grey Blue #29465B ΔE 0.059
- Twilight Blue #0A437A ΔE 0.063
- Space Cadet #2B2D42 ΔE 0.064
- Gunmetal #293241 ΔE 0.065
- Marine #042E60 ΔE 0.067
Use #373563 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.