#51557D
Closest named color: Dusk (#4E5481). oklch(46.3% 0.065 279.1), rgb(81, 85, 125).
Aa
White text reads best on this color (7.12:1).
About this color
#51557D is a medium-dark, muted blue. In OKLCH its lightness is 46%, its chroma 0.065 and its hue 279°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk (#4E5481), ΔE 0.009 away. White text reads best on it, at 7.12:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | muted (0.065) |
| Temperature | cool |
| Nearest name | Dusk (#4E5481) |
| Black text | 2.94:1 |
| White text | 7.12:1 |
Values
| HEX | #51557D |
| RGB | rgb(81, 85, 125) |
| HSL | hsl(235, 21%, 40%) |
| OKLCH | oklch(46.3% 0.065 279.1) |
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 #51557D | 7.12:1 | AAA | Lc -89.6 | Fine for body text |
| Black text on #51557D | 2.94:1 | Fails | Lc 19.3 | Dividers and decoration only |
| #51557D text on white | 7.12:1 | AAA | Lc 84.7 | Fine for body text |
| #51557D text on black | 2.94:1 | Fails | Lc -17.3 | 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 700.
-
Step 50
50
#F5F5F8
oklch(97.1% 0.004 286.3)
-
Step 100
100
#E8E9F0
oklch(93.5% 0.009 279.7)
-
Step 200
200
#D6D8E5
oklch(88.5% 0.018 279)
-
Step 300
300
#BCBFD5
oklch(80.9% 0.031 279.5)
-
Step 400
400
#999EC0
oklch(70.7% 0.05 278.5)
-
Step 500
500
#8186B0
oklch(63.2% 0.063 279.1)
-
Step 600
600
#6A6F9C
oklch(55.5% 0.07 279)
-
Step 700
700 (this color)
#51557D
oklch(46.3% 0.065 279.1)
-
Step 800
800
#484C6C
oklch(42.7% 0.053 278.4)
-
Step 900
900
#3D3F58
oklch(37.7% 0.043 280.6)
-
Step 950
950
#232533
oklch(26.9% 0.026 278.2)
#51557D 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) | #495A7F | 0.017 |
| Deuteranopia (no green cones) | #46567C | 0.016 |
| Tritanopia (no blue cones) | #455D63 | 0.059 |
| Achromatopsia (no color) | #585858 | 0.065 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51557D
#51557D
oklch(46.3% 0.065 279.1)
- #625A2C
#625A2C
oklch(46.4% 0.066 99.6)
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 #51557D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk #4E5481 ΔE 0.009
- Dusty Grape #545775 ΔE 0.017
- Twilight #4E518B ΔE 0.029
- YInMn Blue #415A77 ΔE 0.029
- Dusky Blue #475F94 ΔE 0.042
- Denim Blue #3B5B92 ΔE 0.042
- Light Navy Blue #2E5A88 ΔE 0.045
- Denim #3B638C ΔE 0.047
Use #51557D 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.