#42518F
Closest named color: Twilight (#4E518B). oklch(45.3% 0.103 271.5), rgb(66, 81, 143).
Aa
White text reads best on this color (7.48:1).
About this color
#42518F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 45%, its chroma 0.103 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.018 away. White text reads best on it, at 7.48:1.
| Hue family | Blues |
| Lightness | medium-dark (45%) |
| Chroma | moderately saturated (0.103) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.80:1 |
| White text | 7.48:1 |
Values
| HEX | #42518F |
| RGB | rgb(66, 81, 143) |
| HSL | hsl(228, 37%, 41%) |
| OKLCH | oklch(45.3% 0.103 271.5) |
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 #42518F | 7.48:1 | AAA | Lc -90.7 | Preferred for body text |
| Black text on #42518F | 2.80:1 | Fails | Lc 18.1 | Dividers and decoration only |
| #42518F text on white | 7.48:1 | AAA | Lc 85.9 | Fine for body text |
| #42518F text on black | 2.80:1 | Fails | Lc -16.2 | 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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5E9F6
oklch(93.5% 0.018 272.3)
-
Step 200
200
#D1D8F0
oklch(88.4% 0.034 272.8)
-
Step 300
300
#B2BFE8
oklch(80.8% 0.06 271.2)
-
Step 400
400
#8B9DDD
oklch(70.7% 0.096 271.7)
-
Step 500
500
#6F84D4
oklch(63.2% 0.123 271.4)
-
Step 600
600
#586CC1
oklch(55.6% 0.134 271.5)
-
Step 700
700
#485AA6
oklch(49.1% 0.123 271.2)
-
Step 800
800 (this color)
#42518F
oklch(45.3% 0.103 271.5)
-
Step 900
900
#323E6C
oklch(37.7% 0.08 271.1)
-
Step 950
950
#1E253F
oklch(27.1% 0.049 271.4)
#42518F 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) | #375891 | 0.022 |
| Deuteranopia (no green cones) | #2F528E | 0.023 |
| Tritanopia (no blue cones) | #1E5E69 | 0.091 |
| Achromatopsia (no color) | #555555 | 0.103 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42518F
#42518F
oklch(45.3% 0.103 271.5)
- #695400
#695400
oklch(45.4% 0.093 92)
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 #42518F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.018
- Denim Blue #3B5B92 ΔE 0.028
- Dusk Blue #26538D ΔE 0.031
- Dusk #4E5481 ΔE 0.031
- Light Navy Blue #2E5A88 ΔE 0.036
- Dusky Blue #475F94 ΔE 0.041
- Blueberry #464196 ΔE 0.046
- Light Navy #155084 ΔE 0.050
Use #42518F 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.