#517AD2
Closest named color: Windows Blue (#3778BF). oklch(59.2% 0.142 263.8), rgb(81, 122, 210).
Aa
Black text reads best on this color (5.06:1).
About this color
#517AD2 is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.142 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.040 away. Black text reads best on it, at 5.06:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.142) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.06:1 |
| White text | 4.14:1 |
Values
| HEX | #517AD2 |
| RGB | rgb(81, 122, 210) |
| HSL | hsl(221, 59%, 57%) |
| OKLCH | oklch(59.2% 0.142 263.8) |
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 #517AD2 | 4.14:1 | AA large text | Lc -73.8 | Content text, not long reading |
| Black text on #517AD2 | 5.06:1 | AA | Lc 35.8 | Non-text elements, placeholder text |
| #517AD2 text on white | 4.14:1 | AA large text | Lc 68.3 | Content text, not long reading |
| #517AD2 text on black | 5.06:1 | AA | Lc -33.4 | 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
#F2F5FB
oklch(97% 0.009 264.5)
-
Step 100
100
#E4EAF7
oklch(93.6% 0.019 266)
-
Step 200
200
#CDDAF1
oklch(88.6% 0.035 262)
-
Step 300
300
#ACC1EB
oklch(80.9% 0.064 264.1)
-
Step 400
400
#80A0E1
oklch(70.8% 0.102 263.9)
-
Step 500
500
#6087D8
oklch(63.1% 0.13 263.6)
-
Step 600
600 (this color)
#517AD2
oklch(59.2% 0.142 263.8)
-
Step 700
700
#385CAB
oklch(49% 0.133 263.8)
-
Step 800
800
#2F4C8A
oklch(42.7% 0.109 263.6)
-
Step 900
900
#2A406F
oklch(37.8% 0.085 263.9)
-
Step 950
950
#192641
oklch(27.2% 0.054 263.7)
#517AD2 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) | #5283D5 | 0.024 |
| Deuteranopia (no green cones) | #4077D0 | 0.020 |
| Tritanopia (no blue cones) | #008E9C | 0.121 |
| Achromatopsia (no color) | #7C7C7C | 0.143 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517AD2
#517AD2
oklch(59.2% 0.142 263.8)
- #A07600
#A07600
oklch(59.2% 0.122 83.6)
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 #517AD2, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.040
- Water Blue #0E87CC ΔE 0.052
- Cool Blue #4984B8 ΔE 0.054
- Dark Sky Blue #448EE4 ΔE 0.055
- Soft Blue #6488EA ΔE 0.055
- Royal Blue #4169E1 ΔE 0.057
- Steel Blue #4682B4 ΔE 0.057
- Cornflower #6A79F7 ΔE 0.065
Use #517AD2 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.