#517DCD
Closest named color: Windows Blue (#3778BF). oklch(59.6% 0.132 261.5), rgb(81, 125, 205).
Aa
Black text reads best on this color (5.16:1).
About this color
#517DCD is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.132 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.037 away. Black text reads best on it, at 5.16:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.132) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.16:1 |
| White text | 4.06:1 |
Values
| HEX | #517DCD |
| RGB | rgb(81, 125, 205) |
| HSL | hsl(219, 55%, 56%) |
| OKLCH | oklch(59.6% 0.132 261.5) |
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 #517DCD | 4.06:1 | AA large text | Lc -73.2 | Content text, not long reading |
| Black text on #517DCD | 5.16:1 | AA | Lc 36.4 | Non-text elements, placeholder text |
| #517DCD text on white | 4.06:1 | AA large text | Lc 67.7 | Content text, not long reading |
| #517DCD text on black | 5.16:1 | AA | Lc -34.0 | 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 500.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CCDAF2
oklch(88.5% 0.036 261.3)
-
Step 300
300
#AAC2EB
oklch(81% 0.064 261.1)
-
Step 400
400
#7CA1E1
oklch(70.7% 0.103 261)
-
Step 500
500 (this color)
#517DCD
oklch(59.6% 0.132 261.5)
-
Step 600
600
#4170C6
oklch(55.6% 0.143 261.4)
-
Step 700
700
#335DAB
oklch(49% 0.134 261.5)
-
Step 800
800
#2B4D8B
oklch(42.8% 0.11 261.3)
-
Step 900
900
#27406F
oklch(37.6% 0.087 261.9)
-
Step 950
950
#172641
oklch(27% 0.055 261.4)
#517DCD 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) | #5A84D0 | 0.023 |
| Deuteranopia (no green cones) | #4A79CB | 0.014 |
| Tritanopia (no blue cones) | #008F9B | 0.113 |
| Achromatopsia (no color) | #7E7E7E | 0.132 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517DCD
#517DCD
oklch(59.6% 0.132 261.5)
- #A47600
#A47600
oklch(59.6% 0.123 81.3)
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 #517DCD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.037
- Cool Blue #4984B8 ΔE 0.042
- Water Blue #0E87CC ΔE 0.045
- Steel Blue #4682B4 ΔE 0.046
- Dark Sky Blue #448EE4 ΔE 0.051
- Soft Blue #6488EA ΔE 0.056
- Off Blue #5684AE ΔE 0.057
- Faded Blue #658CBB ΔE 0.061
Use #517DCD 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.