#517DDB
Closest named color: Soft Blue (#6488EA). oklch(60.4% 0.151 263.6), rgb(81, 125, 219).
Aa
Black text reads best on this color (5.30:1).
About this color
#517DDB is a medium-dark, vivid blue. In OKLCH its lightness is 60%, its chroma 0.151 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Soft Blue (#6488EA), ΔE 0.043 away. Black text reads best on it, at 5.30:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | vivid (0.151) |
| Temperature | cool |
| Nearest name | Soft Blue (#6488EA) |
| Black text | 5.30:1 |
| White text | 3.95:1 |
Values
| HEX | #517DDB |
| RGB | rgb(81, 125, 219) |
| HSL | hsl(221, 66%, 59%) |
| OKLCH | oklch(60.4% 0.151 263.6) |
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 #517DDB | 3.95:1 | AA large text | Lc -72.2 | Content text, not long reading |
| Black text on #517DDB | 5.30:1 | AA | Lc 37.4 | Non-text elements, placeholder text |
| #517DDB text on white | 3.95:1 | AA large text | Lc 66.7 | Content text, not long reading |
| #517DDB text on black | 5.30:1 | AA | Lc -35.0 | 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
#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
#A8C1F1
oklch(80.9% 0.074 263.3)
-
Step 400
400
#7A9FEB
oklch(70.7% 0.119 263.8)
-
Step 500
500 (this color)
#517DDB
oklch(60.4% 0.151 263.6)
-
Step 600
600
#3F6DD2
oklch(55.6% 0.164 263.6)
-
Step 700
700
#315AB6
oklch(49% 0.153 263.7)
-
Step 800
800
#294A93
oklch(42.6% 0.126 263.6)
-
Step 900
900
#253F75
oklch(37.7% 0.098 263.2)
-
Step 950
950
#162545
oklch(27% 0.063 263.8)
#517DDB 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) | #5187DF | 0.026 |
| Deuteranopia (no green cones) | #3C7AD9 | 0.023 |
| Tritanopia (no blue cones) | #0092A1 | 0.127 |
| Achromatopsia (no color) | #808080 | 0.151 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517DDB
#517DDB
oklch(60.4% 0.151 263.6)
- #A57900
#A57900
oklch(60.4% 0.124 83)
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 #517DDB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Soft Blue #6488EA ΔE 0.043
- Dark Sky Blue #448EE4 ΔE 0.044
- Windows Blue #3778BF ΔE 0.052
- Cornflower #6A79F7 ΔE 0.054
- Water Blue #0E87CC ΔE 0.054
- Royal Blue #4169E1 ΔE 0.058
- Clear Blue #247AFD ΔE 0.062
- Cool Blue #4984B8 ΔE 0.062
Use #517DDB 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.