#51559F
Closest named color: Twilight (#4E518B). oklch(48.3% 0.117 278.7), rgb(81, 85, 159).
Aa
White text reads best on this color (6.66:1).
About this color
#51559F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 48%, its chroma 0.117 and its hue 279°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.033 away. White text reads best on it, at 6.66:1.
| Hue family | Blues |
| Lightness | medium-dark (48%) |
| Chroma | moderately saturated (0.117) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 3.14:1 |
| White text | 6.66:1 |
Values
| HEX | #51559F |
| RGB | rgb(81, 85, 159) |
| HSL | hsl(237, 33%, 47%) |
| OKLCH | oklch(48.3% 0.117 278.7) |
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 #51559F | 6.66:1 | AA | Lc -87.8 | Fine for body text |
| Black text on #51559F | 3.14:1 | AA large text | Lc 21.3 | Dividers and decoration only |
| #51559F text on white | 6.66:1 | AA | Lc 82.8 | Fine for body text |
| #51559F text on black | 3.14:1 | AA large text | Lc -19.1 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E7E9F5
oklch(93.6% 0.016 278.5)
-
Step 200
200
#D4D8EE
oklch(88.6% 0.03 277.6)
-
Step 300
300
#B8BEE6
oklch(81% 0.057 278.4)
-
Step 400
400
#949BD9
oklch(70.7% 0.091 278.8)
-
Step 500
500
#7A81CE
oklch(63% 0.116 278.6)
-
Step 600
600
#6469BB
oklch(55.5% 0.126 278.8)
-
Step 700
700 (this color)
#51559F
oklch(48.3% 0.117 278.7)
-
Step 800
800
#444883
oklch(42.8% 0.097 278.5)
-
Step 900
900
#393D69
oklch(37.8% 0.075 278.2)
-
Step 950
950
#21243D
oklch(27% 0.047 277.6)
#51559F 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) | #365FA2 | 0.039 |
| Deuteranopia (no green cones) | #30599D | 0.041 |
| Tritanopia (no blue cones) | #346572 | 0.103 |
| Achromatopsia (no color) | #5C5C5C | 0.118 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51559F
#51559F
oklch(48.3% 0.117 278.7)
- #6D5E00
#6D5E00
oklch(48.2% 0.1 98.3)
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 #51559F, closest first.
No curated palette has a color within ΔE 0.04 of #51559F.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.033
- Dusky Blue #475F94 ΔE 0.038
- Denim Blue #3B5B92 ΔE 0.040
- Dusk #4E5481 ΔE 0.049
- Blueberry #464196 ΔE 0.058
- French Blue #436BAD ΔE 0.060
- Denim #3B638C ΔE 0.061
- Light Navy Blue #2E5A88 ΔE 0.061
Use #51559F 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.