#517DA5
Closest named color: Stormy Blue (#507B9C). oklch(57.4% 0.079 247.1), rgb(81, 125, 165).
Aa
Black text reads best on this color (4.82:1).
About this color
#517DA5 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.079 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Stormy Blue (#507B9C), ΔE 0.014 away. Black text reads best on it, at 4.82:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.079) |
| Temperature | cool |
| Nearest name | Stormy Blue (#507B9C) |
| Black text | 4.82:1 |
| White text | 4.35:1 |
Values
| HEX | #517DA5 |
| RGB | rgb(81, 125, 165) |
| HSL | hsl(209, 34%, 48%) |
| OKLCH | oklch(57.4% 0.079 247.1) |
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 #517DA5 | 4.35:1 | AA large text | Lc -75.5 | Fine for body text |
| Black text on #517DA5 | 4.82:1 | AA | Lc 34.0 | Non-text elements, placeholder text |
| #517DA5 text on white | 4.35:1 | AA large text | Lc 70.0 | Content text, not long reading |
| #517DA5 text on black | 4.82:1 | AA | Lc -31.6 | 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
#F3F6F8
oklch(97.1% 0.004 236.5)
-
Step 100
100
#E5EBF0
oklch(93.7% 0.009 242.8)
-
Step 200
200
#CFDBE6
oklch(88.6% 0.02 245.7)
-
Step 300
300
#AFC3D7
oklch(80.8% 0.036 248.3)
-
Step 400
400
#84A4C3
oklch(70.6% 0.058 247.8)
-
Step 500
500
#658EB3
oklch(63.1% 0.072 246.5)
-
Step 600
600 (this color)
#517DA5
oklch(57.4% 0.079 247.1)
-
Step 700
700
#3D6488
oklch(49% 0.073 247.6)
-
Step 800
800
#32526F
oklch(42.7% 0.061 247.1)
-
Step 900
900
#2C445A
oklch(37.7% 0.048 247.1)
-
Step 950
950
#1A2834
oklch(27% 0.03 245.1)
#517DA5 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) | #6C7EA7 | 0.034 |
| Deuteranopia (no green cones) | #6275A4 | 0.028 |
| Tritanopia (no blue cones) | #27868B | 0.066 |
| Achromatopsia (no color) | #797979 | 0.079 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517DA5
#517DA5
oklch(57.4% 0.079 247.1)
- #986F44
#986F44
oklch(57.4% 0.079 66.5)
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 #517DA5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Stormy Blue #507B9C ΔE 0.014
- Cerulean #457B9D ΔE 0.019
- Off Blue #5684AE ΔE 0.023
- Steel Blue #4682B4 ΔE 0.025
- Dull Blue #49759C ΔE 0.027
- Dusty Blue #5A86AD ΔE 0.030
- Cool Blue #4984B8 ΔE 0.031
- Flat Blue #3C73A8 ΔE 0.040
Use #517DA5 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.