#42557D
Closest named color: Dusk (#4E5481). oklch(45.2% 0.07 264.3), rgb(66, 85, 125).
Aa
White text reads best on this color (7.42:1).
About this color
#42557D is a medium-dark, moderately saturated blue. In OKLCH its lightness is 45%, its chroma 0.070 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk (#4E5481), ΔE 0.019 away. White text reads best on it, at 7.42:1.
| Hue family | Blues |
| Lightness | medium-dark (45%) |
| Chroma | moderately saturated (0.070) |
| Temperature | cool |
| Nearest name | Dusk (#4E5481) |
| Black text | 2.82:1 |
| White text | 7.42:1 |
Values
| HEX | #42557D |
| RGB | rgb(66, 85, 125) |
| HSL | hsl(221, 31%, 37%) |
| OKLCH | oklch(45.2% 0.07 264.3) |
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 #42557D | 7.42:1 | AAA | Lc -90.6 | Preferred for body text |
| Black text on #42557D | 2.82:1 | Fails | Lc 18.3 | Dividers and decoration only |
| #42557D text on white | 7.42:1 | AAA | Lc 85.7 | Fine for body text |
| #42557D text on black | 2.82:1 | Fails | Lc -16.3 | Dividers and decoration only |
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 800.
-
Step 50
50
#F3F5F9
oklch(97% 0.006 264.5)
-
Step 100
100
#E6EAF2
oklch(93.6% 0.012 264.5)
-
Step 200
200
#D2D9E9
oklch(88.5% 0.023 266.9)
-
Step 300
300
#B3C1DC
oklch(80.9% 0.041 263.6)
-
Step 400
400
#8CA1CA
oklch(70.8% 0.065 263.6)
-
Step 500
500
#7089BD
oklch(63.1% 0.084 264.4)
-
Step 600
600
#5872A9
oklch(55.6% 0.091 264.3)
-
Step 700
700
#485F91
oklch(49% 0.085 264.6)
-
Step 800
800 (this color)
#42557D
oklch(45.2% 0.07 264.3)
-
Step 900
900
#33415F
oklch(37.7% 0.055 264.7)
-
Step 950
950
#1E2638
oklch(27% 0.036 265.6)
#42557D 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) | #46587F | 0.011 |
| Deuteranopia (no green cones) | #40537C | 0.007 |
| Tritanopia (no blue cones) | #2C5D63 | 0.062 |
| Achromatopsia (no color) | #555555 | 0.070 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42557D
#42557D
oklch(45.2% 0.07 264.3)
- #685224
#685224
oklch(45.1% 0.07 83.7)
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 #42557D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk #4E5481 ΔE 0.019
- YInMn Blue #415A77 ΔE 0.020
- Light Navy Blue #2E5A88 ΔE 0.028
- Dusty Grape #545775 ΔE 0.030
- Twilight #4E518B ΔE 0.033
- Denim Blue #3B5B92 ΔE 0.035
- Dusk Blue #26538D ΔE 0.041
- Denim #3B638C ΔE 0.043
Use #42557D 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.