#517DA0
Closest named color: Stormy Blue (#507B9C). oklch(57.2% 0.073 243.5), rgb(81, 125, 160).
Aa
Black text reads best on this color (4.79:1).
About this color
#517DA0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.073 and its hue 244°. Its hue sits on the cool side of the wheel. The nearest named color is Stormy Blue (#507B9C), ΔE 0.008 away. Black text reads best on it, at 4.79:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.073) |
| Temperature | cool |
| Nearest name | Stormy Blue (#507B9C) |
| Black text | 4.79:1 |
| White text | 4.38:1 |
Values
| HEX | #517DA0 |
| RGB | rgb(81, 125, 160) |
| HSL | hsl(207, 33%, 47%) |
| OKLCH | oklch(57.2% 0.073 243.5) |
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 #517DA0 | 4.38:1 | AA large text | Lc -75.8 | Fine for body text |
| Black text on #517DA0 | 4.79:1 | AA | Lc 33.8 | Non-text elements, placeholder text |
| #517DA0 text on white | 4.38:1 | AA large text | Lc 70.3 | Content text, not long reading |
| #517DA0 text on black | 4.79:1 | AA | Lc -31.4 | 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
#CFDBE4
oklch(88.5% 0.018 240)
-
Step 300
300
#AFC4D5
oklch(81% 0.033 242.4)
-
Step 400
400
#85A5BF
oklch(70.7% 0.052 243)
-
Step 500
500
#668EAF
oklch(63% 0.067 244)
-
Step 600
600 (this color)
#517DA0
oklch(57.2% 0.073 243.5)
-
Step 700
700
#3D6584
oklch(49.1% 0.067 243.1)
-
Step 800
800
#33526C
oklch(42.6% 0.057 245)
-
Step 900
900
#2D4457
oklch(37.6% 0.044 244.2)
-
Step 950
950
#1B2833
oklch(27% 0.027 244.6)
#517DA0 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) | #6E7DA2 | 0.036 |
| Deuteranopia (no green cones) | #64759F | 0.030 |
| Tritanopia (no blue cones) | #2C8589 | 0.059 |
| Achromatopsia (no color) | #797979 | 0.073 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #517DA0
#517DA0
oklch(57.2% 0.073 243.5)
- #976F49
#976F49
oklch(57.3% 0.074 64)
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 #517DA0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Stormy Blue #507B9C ΔE 0.008
- Cerulean #457B9D ΔE 0.015
- Dull Blue #49759C ΔE 0.026
- Off Blue #5684AE ΔE 0.027
- Steel Blue #4682B4 ΔE 0.031
- Dusty Blue #5A86AD ΔE 0.032
- Grey Blue #647D8E ΔE 0.034
- Metallic Blue #4F738E ΔE 0.036
Use #517DA0 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.