#5173CA
Closest named color: Windows Blue (#3778BF). oklch(57.3% 0.14 266.1), rgb(81, 115, 202).
Aa
Black text reads best on this color (4.65:1).
About this color
#5173CA is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.140 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.034 away. Black text reads best on it, at 4.65:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.140) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.65:1 |
| White text | 4.51:1 |
Values
| HEX | #5173CA |
| RGB | rgb(81, 115, 202) |
| HSL | hsl(223, 53%, 55%) |
| OKLCH | oklch(57.3% 0.14 266.1) |
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 #5173CA | 4.51:1 | AA | Lc -76.6 | Fine for body text |
| Black text on #5173CA | 4.65:1 | AA | Lc 33.0 | Non-text elements, placeholder text |
| #5173CA text on white | 4.51:1 | AA | Lc 71.1 | Content text, not long reading |
| #5173CA text on black | 4.65:1 | AA | Lc -30.6 | 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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E4EAF7
oklch(93.6% 0.019 266)
-
Step 200
200
#CED9F1
oklch(88.4% 0.035 266)
-
Step 300
300
#AEC0EA
oklch(80.8% 0.063 266.8)
-
Step 400
400
#839FE0
oklch(70.7% 0.101 266)
-
Step 500
500
#6586D7
oklch(63.1% 0.128 266.1)
-
Step 600
600 (this color)
#5173CA
oklch(57.3% 0.14 266.1)
-
Step 700
700
#3E5CAA
oklch(49.2% 0.13 266)
-
Step 800
800
#334B89
oklch(42.6% 0.107 266.1)
-
Step 900
900
#2C3F6E
oklch(37.6% 0.084 265.9)
-
Step 950
950
#1A2540
oklch(26.9% 0.053 266.2)
#5173CA 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) | #4C7CCD | 0.024 |
| Deuteranopia (no green cones) | #3B71C8 | 0.024 |
| Tritanopia (no blue cones) | #008695 | 0.120 |
| Achromatopsia (no color) | #767676 | 0.140 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5173CA
#5173CA
oklch(57.3% 0.14 266.1)
- #977200
#977200
oklch(57.3% 0.117 85.9)
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 #5173CA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.034
- Royal Blue #4169E1 ΔE 0.050
- French Blue #436BAD ΔE 0.052
- Dark Periwinkle #665FD1 ΔE 0.056
- Flat Blue #3C73A8 ΔE 0.059
- Cool Blue #4984B8 ΔE 0.060
- Steel Blue #4682B4 ΔE 0.060
- Mid Blue #276AB3 ΔE 0.061
Use #5173CA 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.