#559DEF
Closest named color: Cornflower Blue (#6495ED). oklch(68.6% 0.142 253.2), rgb(85, 157, 239).
Aa
Black text reads best on this color (7.45:1).
About this color
#559DEF is a medium-light, vivid blue. In OKLCH its lightness is 69%, its chroma 0.142 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower Blue (#6495ED), ΔE 0.023 away. Black text reads best on it, at 7.45:1.
| Hue family | Blues |
| Lightness | medium-light (69%) |
| Chroma | vivid (0.142) |
| Temperature | cool |
| Nearest name | Cornflower Blue (#6495ED) |
| Black text | 7.45:1 |
| White text | 2.81:1 |
Values
| HEX | #559DEF |
| RGB | rgb(85, 157, 239) |
| HSL | hsl(212, 83%, 64%) |
| OKLCH | oklch(68.6% 0.142 253.2) |
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 #559DEF | 2.81:1 | Fails | Lc -59.1 | Large or bold text, headings |
| Black text on #559DEF | 7.45:1 | AAA | Lc 50.2 | Large or bold text, headings |
| #559DEF text on white | 2.81:1 | Fails | Lc 53.9 | Large or bold text, headings |
| #559DEF text on black | 7.45:1 | AAA | Lc -48.0 | Large or bold text, headings |
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 400.
-
Step 50
50
#F0F6FD
oklch(97.1% 0.011 252.1)
-
Step 100
100
#DEEBFB
oklch(93.5% 0.026 253.6)
-
Step 200
200
#C3DCFA
oklch(88.6% 0.049 253.1)
-
Step 300
300
#98C4F9
oklch(80.8% 0.089 253.5)
-
Step 400
400 (this color)
#559DEF
oklch(68.6% 0.142 253.2)
-
Step 500
500
#208AF3
oklch(63.2% 0.182 253.2)
-
Step 600
600
#0073D4
oklch(55.6% 0.172 253.1)
-
Step 700
700
#0060B3
oklch(49% 0.152 253.2)
-
Step 800
800
#004F94
oklch(42.8% 0.131 252.8)
-
Step 900
900
#00417D
oklch(37.6% 0.117 253.3)
-
Step 950
950
#05274A
oklch(27.1% 0.075 252.9)
#559DEF 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) | #79A2F2 | 0.041 |
| Deuteranopia (no green cones) | #6493ED | 0.028 |
| Tritanopia (no blue cones) | #00B0BB | 0.113 |
| Achromatopsia (no color) | #9A9A9A | 0.142 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #559DEF
#559DEF
oklch(68.6% 0.142 253.2)
- #CE8A13
#CE8A13
oklch(68.6% 0.142 73.2)
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 #559DEF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cornflower Blue #6495ED ΔE 0.023
- Chefchaouen Blue #4895EF ΔE 0.026
- Dark Sky Blue #448EE4 ΔE 0.046
- Soft Blue #6488EA ΔE 0.054
- Dodger Blue #1E90FF ΔE 0.059
- Periwinkle Blue #8F99FB ΔE 0.068
- Perrywinkle #8F8CE7 ΔE 0.073
- Lavender Blue #8B88F8 ΔE 0.079
Use #559DEF 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.