#517CC7
Closest named color: Windows Blue (#3778BF). oklch(59% 0.125 260.9), rgb(81, 124, 199).
Aa
Black text reads best on this color (5.05:1).
About this color
#517CC7 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.125 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.031 away. Black text reads best on it, at 5.05:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.05:1 |
| White text | 4.15:1 |
Values
| HEX | #517CC7 |
| RGB | rgb(81, 124, 199) |
| HSL | hsl(218, 51%, 55%) |
| OKLCH | oklch(59% 0.125 260.9) |
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 #517CC7 | 4.15:1 | AA large text | Lc -73.9 | Content text, not long reading |
| Black text on #517CC7 | 5.05:1 | AA | Lc 35.7 | Non-text elements, placeholder text |
| #517CC7 text on white | 4.15:1 | AA large text | Lc 68.4 | Content text, not long reading |
| #517CC7 text on black | 5.05:1 | AA | Lc -33.3 | Non-text elements, placeholder text |
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 600.
-
Step 50
50
#F3F6FB
oklch(97.2% 0.007 260.7)
-
Step 100
100
#E4EAF5
oklch(93.6% 0.016 262.8)
-
Step 200
200
#CEDAEE
oklch(88.5% 0.03 260.7)
-
Step 300
300
#ACC2E6
oklch(81% 0.056 260.2)
-
Step 400
400
#81A1D9
oklch(70.7% 0.09 261.3)
-
Step 500
500
#6189CF
oklch(63.1% 0.115 261)
-
Step 600
600 (this color)
#517CC7
oklch(59% 0.125 260.9)
-
Step 700
700
#395FA2
oklch(49.1% 0.116 260.9)
-
Step 800
800
#2F4E83
oklch(42.7% 0.096 260.5)
-
Step 900
900
#2A4169
oklch(37.7% 0.075 260.9)
-
Step 950
950
#19263E
oklch(27% 0.049 262)
#517CC7 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) | #5C82CA | 0.022 |
| Deuteranopia (no green cones) | #4D77C5 | 0.015 |
| Tritanopia (no blue cones) | #008D98 | 0.109 |
| Achromatopsia (no color) | #7C7C7C | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517CC7
#517CC7
oklch(59% 0.125 260.9)
- #A27400
#A27400
oklch(59% 0.122 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 #517CC7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.031
- Cool Blue #4984B8 ΔE 0.037
- Steel Blue #4682B4 ΔE 0.039
- Water Blue #0E87CC ΔE 0.045
- Off Blue #5684AE ΔE 0.050
- Dusty Blue #5A86AD ΔE 0.056
- Flat Blue #3C73A8 ΔE 0.058
- Dark Sky Blue #448EE4 ΔE 0.058
Use #517CC7 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.