#42577C
Closest named color: YInMn Blue (#415A77). oklch(45.6% 0.066 261.4), rgb(66, 87, 124).
Aa
White text reads best on this color (7.27:1).
About this color
#42577C is a medium-dark, muted blue. In OKLCH its lightness is 46%, its chroma 0.066 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is YInMn Blue (#415A77), ΔE 0.014 away. White text reads best on it, at 7.27:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | muted (0.066) |
| Temperature | cool |
| Nearest name | YInMn Blue (#415A77) |
| Black text | 2.88:1 |
| White text | 7.27:1 |
Values
| HEX | #42577C |
| RGB | rgb(66, 87, 124) |
| HSL | hsl(218, 31%, 37%) |
| OKLCH | oklch(45.6% 0.066 261.4) |
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 #42577C | 7.27:1 | AAA | Lc -90.1 | Preferred for body text |
| Black text on #42577C | 2.88:1 | Fails | Lc 18.8 | Dividers and decoration only |
| #42577C text on white | 7.27:1 | AAA | Lc 85.2 | Fine for body text |
| #42577C text on black | 2.88:1 | Fails | Lc -16.8 | 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
#D1DAE8
oklch(88.6% 0.022 259.2)
-
Step 300
300
#B3C1DA
oklch(80.8% 0.039 262.1)
-
Step 400
400
#8BA1C8
oklch(70.6% 0.063 261.8)
-
Step 500
500
#6F8ABA
oklch(63.2% 0.079 261.6)
-
Step 600
600
#5773A6
oklch(55.6% 0.086 261.9)
-
Step 700
700
#47618E
oklch(49.2% 0.079 261)
-
Step 800
800 (this color)
#42577C
oklch(45.6% 0.066 261.4)
-
Step 900
900
#32425D
oklch(37.8% 0.051 260.6)
-
Step 950
950
#1D2737
oklch(27.1% 0.033 259.6)
#42577C 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) | #495A7E | 0.014 |
| Deuteranopia (no green cones) | #43547B | 0.009 |
| Tritanopia (no blue cones) | #2C5F64 | 0.059 |
| Achromatopsia (no color) | #575757 | 0.066 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42577C
#42577C
oklch(45.6% 0.066 261.4)
- #6A5329
#6A5329
oklch(45.6% 0.066 80.9)
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 #42577C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- YInMn Blue #415A77 ΔE 0.014
- Dusk #4E5481 ΔE 0.021
- Dusty Grape #545775 ΔE 0.027
- Light Navy Blue #2E5A88 ΔE 0.027
- Denim Blue #3B5B92 ΔE 0.036
- Twilight #4E518B ΔE 0.037
- Denim #3B638C ΔE 0.038
- Dusky Blue #475F94 ΔE 0.043
Use #42577C 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.