#517CDB
Closest named color: Soft Blue (#6488EA). oklch(60.2% 0.152 264), rgb(81, 124, 219).
Aa
Black text reads best on this color (5.25:1).
About this color
#517CDB is a medium-dark, vivid blue. In OKLCH its lightness is 60%, its chroma 0.152 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Soft Blue (#6488EA), ΔE 0.045 away. Black text reads best on it, at 5.25:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Soft Blue (#6488EA) |
| Black text | 5.25:1 |
| White text | 3.99:1 |
Values
| HEX | #517CDB |
| RGB | rgb(81, 124, 219) |
| HSL | hsl(221, 66%, 59%) |
| OKLCH | oklch(60.2% 0.152 264) |
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 #517CDB | 3.99:1 | AA large text | Lc -72.5 | Content text, not long reading |
| Black text on #517CDB | 5.25:1 | AA | Lc 37.1 | Non-text elements, placeholder text |
| #517CDB text on white | 3.99:1 | AA large text | Lc 67.0 | Content text, not long reading |
| #517CDB text on black | 5.25:1 | AA | Lc -34.7 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E3EAF9
oklch(93.6% 0.022 265.8)
-
Step 200
200
#CBDAF5
oklch(88.6% 0.041 262.3)
-
Step 300
300
#A8C1F2
oklch(80.9% 0.075 263.7)
-
Step 400
400
#7A9FEB
oklch(70.7% 0.119 263.8)
-
Step 500
500 (this color)
#517CDB
oklch(60.2% 0.152 264)
-
Step 600
600
#406CD3
oklch(55.5% 0.166 264.3)
-
Step 700
700
#325AB7
oklch(49.1% 0.154 264)
-
Step 800
800
#2A4A94
oklch(42.7% 0.128 264.1)
-
Step 900
900
#263F76
oklch(37.8% 0.099 263.9)
-
Step 950
950
#162545
oklch(27% 0.063 263.8)
#517CDB 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) | #5086DF | 0.026 |
| Deuteranopia (no green cones) | #3A79D9 | 0.024 |
| Tritanopia (no blue cones) | #0092A1 | 0.129 |
| Achromatopsia (no color) | #7F7F7F | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517CDB
#517CDB
oklch(60.2% 0.152 264)
- #A37900
#A37900
oklch(60.1% 0.123 84.2)
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 #517CDB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Soft Blue #6488EA ΔE 0.045
- Dark Sky Blue #448EE4 ΔE 0.047
- Windows Blue #3778BF ΔE 0.052
- Cornflower #6A79F7 ΔE 0.053
- Water Blue #0E87CC ΔE 0.055
- Royal Blue #4169E1 ΔE 0.056
- Clear Blue #247AFD ΔE 0.061
- Cool Blue #4984B8 ΔE 0.063
Use #517CDB 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.