#017CC9
Closest named color: Windows Blue (#3778BF). oklch(57% 0.149 246.8), rgb(1, 124, 201).
Aa
Black text reads best on this color (4.72:1).
About this color
#017CC9 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.149 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.025 away. Black text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.149) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.72:1 |
| White text | 4.44:1 |
Values
| HEX | #017CC9 |
| RGB | rgb(1, 124, 201) |
| HSL | hsl(203, 99%, 40%) |
| OKLCH | oklch(57% 0.149 246.8) |
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 #017CC9 | 4.44:1 | AA large text | Lc -75.6 | Fine for body text |
| Black text on #017CC9 | 4.72:1 | AA | Lc 34.0 | Non-text elements, placeholder text |
| #017CC9 text on white | 4.44:1 | AA large text | Lc 70.1 | Content text, not long reading |
| #017CC9 text on black | 4.72:1 | AA | Lc -31.5 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E0EBF6
oklch(93.5% 0.019 248)
-
Step 200
200
#C6DCF1
oklch(88.5% 0.037 247)
-
Step 300
300
#9EC5EA
oklch(80.8% 0.067 247.3)
-
Step 400
400
#66A7E0
oklch(70.8% 0.107 246.5)
-
Step 500
500
#368FD7
oklch(63.1% 0.137 246.9)
-
Step 600
600 (this color)
#017CC9
oklch(57% 0.149 246.8)
-
Step 700
700
#0065A5
oklch(49.2% 0.128 246.7)
-
Step 800
800
#005288
oklch(42.7% 0.112 246.9)
-
Step 900
900
#0E446E
oklch(37.6% 0.09 247.4)
-
Step 950
950
#0B2840
oklch(26.9% 0.056 247)
#017CC9 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) | #5680CC | 0.054 |
| Deuteranopia (no green cones) | #3970C8 | 0.037 |
| Tritanopia (no blue cones) | #008F99 | 0.105 |
| Achromatopsia (no color) | #787878 | 0.149 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #017CC9
#017CC9
oklch(57% 0.149 246.8)
- #A86600
#A86600
oklch(57% 0.126 66.8)
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 #017CC9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.025
- Water Blue #0E87CC ΔE 0.031
- Nice Blue #107AB0 ΔE 0.038
- Steel Blue #4682B4 ΔE 0.053
- Cool Blue #4984B8 ΔE 0.054
- Mid Blue #276AB3 ΔE 0.055
- Flat Blue #3C73A8 ΔE 0.055
- Blue NCS #118AB2 ΔE 0.060
Use #017CC9 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.