#517EB8
Closest named color: Steel Blue (#4682B4). oklch(58.6% 0.103 255.3), rgb(81, 126, 184).
Aa
Black text reads best on this color (5.02:1).
About this color
#517EB8 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.103 and its hue 255°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.017 away. Black text reads best on it, at 5.02:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.103) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 5.02:1 |
| White text | 4.17:1 |
Values
| HEX | #517EB8 |
| RGB | rgb(81, 126, 184) |
| HSL | hsl(214, 42%, 52%) |
| OKLCH | oklch(58.6% 0.103 255.3) |
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 #517EB8 | 4.17:1 | AA large text | Lc -74.1 | Content text, not long reading |
| Black text on #517EB8 | 5.02:1 | AA | Lc 35.4 | Non-text elements, placeholder text |
| #517EB8 text on white | 4.17:1 | AA large text | Lc 68.6 | Content text, not long reading |
| #517EB8 text on black | 5.02:1 | AA | Lc -33.0 | 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 600.
-
Step 50
50
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E4EAF3
oklch(93.5% 0.014 258.3)
-
Step 200
200
#CEDAEA
oklch(88.4% 0.026 255.6)
-
Step 300
300
#ADC3DF
oklch(81% 0.046 254.5)
-
Step 400
400
#82A3CE
oklch(70.7% 0.073 255.2)
-
Step 500
500
#628CC2
oklch(63.2% 0.094 255.1)
-
Step 600
600 (this color)
#517EB8
oklch(58.6% 0.103 255.3)
-
Step 700
700
#3A6296
oklch(49.1% 0.095 255.6)
-
Step 800
800
#305079
oklch(42.6% 0.078 255.2)
-
Step 900
900
#2B4362
oklch(37.8% 0.061 255.3)
-
Step 950
950
#192739
oklch(26.9% 0.039 255.1)
#517EB8 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) | #6681BA | 0.027 |
| Deuteranopia (no green cones) | #5977B7 | 0.020 |
| Tritanopia (no blue cones) | #058B93 | 0.090 |
| Achromatopsia (no color) | #7C7C7C | 0.103 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517EB8
#517EB8
oklch(58.6% 0.103 255.3)
- #9F732C
#9F732C
oklch(58.7% 0.103 76)
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 #517EB8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.017
- Cool Blue #4984B8 ΔE 0.018
- Off Blue #5684AE ΔE 0.027
- Windows Blue #3778BF ΔE 0.034
- Dusty Blue #5A86AD ΔE 0.034
- Stormy Blue #507B9C ΔE 0.043
- Cerulean #457B9D ΔE 0.045
- Flat Blue #3C73A8 ΔE 0.045
Use #517EB8 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.