#42497E
Closest named color: Twilight (#4E518B). oklch(42.5% 0.088 276.3), rgb(66, 73, 126).
Aa
White text reads best on this color (8.44:1).
About this color
#42497E is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.088 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.036 away. White text reads best on it, at 8.44:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.48:1 |
| White text | 8.44:1 |
Values
| HEX | #42497E |
| RGB | rgb(66, 73, 126) |
| HSL | hsl(233, 31%, 38%) |
| OKLCH | oklch(42.5% 0.088 276.3) |
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 #42497E | 8.44:1 | AAA | Lc -93.6 | Preferred for body text |
| Black text on #42497E | 2.48:1 | Fails | Lc 15.0 | Not readable |
| #42497E text on white | 8.44:1 | AAA | Lc 89.0 | Fine for body text |
| #42497E text on black | 2.48:1 | Fails | Lc -13.2 | 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 800.
-
Step 50
50
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E7E9F4
oklch(93.6% 0.015 277.8)
-
Step 200
200
#D4D8ED
oklch(88.6% 0.029 277.2)
-
Step 300
300
#B7BEE2
oklch(80.8% 0.051 276.5)
-
Step 400
400
#939CD4
oklch(70.6% 0.083 277)
-
Step 500
500
#7983C9
oklch(63.1% 0.106 276.7)
-
Step 600
600
#626CB5
oklch(55.6% 0.113 276.2)
-
Step 700
700
#515A9C
oklch(49.1% 0.106 275.9)
-
Step 800
800 (this color)
#42497E
oklch(42.5% 0.088 276.3)
-
Step 900
900
#383E66
oklch(37.8% 0.069 276.1)
-
Step 950
950
#21243C
oklch(27% 0.045 277.5)
#42497E 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) | #355080 | 0.024 |
| Deuteranopia (no green cones) | #304B7D | 0.024 |
| Tritanopia (no blue cones) | #2D545D | 0.078 |
| Achromatopsia (no color) | #4D4D4D | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42497E
#42497E
oklch(42.5% 0.088 276.3)
- #5D4E00
#5D4E00
oklch(42.6% 0.088 96.3)
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 #42497E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.036
- Dusk #4E5481 ΔE 0.038
- Dark Slate Blue #483D8B ΔE 0.042
- Dusk Blue #26538D ΔE 0.043
- Light Navy #155084 ΔE 0.047
- Blueberry #464196 ΔE 0.048
- Cobalt #1E488F ΔE 0.050
- Light Navy Blue #2E5A88 ΔE 0.051
Use #42497E 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.