#559DB0
Closest named color: Cadet Blue (#5F9EA0). oklch(65.6% 0.077 217), rgb(85, 157, 176).
Aa
Black text reads best on this color (6.83:1).
About this color
#559DB0 is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 66%, its chroma 0.077 and its hue 217°. Its hue sits on the cool side of the wheel. The nearest named color is Cadet Blue (#5F9EA0), ΔE 0.026 away. Black text reads best on it, at 6.83:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (66%) |
| Chroma | moderately saturated (0.077) |
| Temperature | cool |
| Nearest name | Cadet Blue (#5F9EA0) |
| Black text | 6.83:1 |
| White text | 3.07:1 |
Values
| HEX | #559DB0 |
| RGB | rgb(85, 157, 176) |
| HSL | hsl(193, 37%, 51%) |
| OKLCH | oklch(65.6% 0.077 217) |
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 #559DB0 | 3.07:1 | AA large text | Lc -62.8 | Content text, not long reading |
| Black text on #559DB0 | 6.83:1 | AA | Lc 46.6 | Large or bold text, headings |
| #559DB0 text on white | 3.07:1 | AA large text | Lc 57.5 | Large or bold text, headings |
| #559DB0 text on black | 6.83:1 | AA | Lc -44.3 | 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 500.
-
Step 50
50
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E2ECEF
oklch(93.6% 0.011 217.5)
-
Step 200
200
#CBDDE2
oklch(88.6% 0.021 216.2)
-
Step 300
300
#A6C7D1
oklch(80.9% 0.038 218.1)
-
Step 400
400
#75AAB9
oklch(70.6% 0.06 217.4)
-
Step 500
500 (this color)
#559DB0
oklch(65.6% 0.077 217)
-
Step 600
600
#2B7F93
oklch(55.5% 0.084 216.9)
-
Step 700
700
#1C6B7E
oklch(49% 0.079 217.9)
-
Step 800
800
#1B5866
oklch(42.8% 0.065 216.2)
-
Step 900
900
#1D4853
oklch(37.6% 0.051 217.1)
-
Step 950
950
#122A31
oklch(26.9% 0.033 219.1)
#559DB0 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) | #9099B1 | 0.068 |
| Deuteranopia (no green cones) | #828FB0 | 0.060 |
| Tritanopia (no blue cones) | #1AA4A3 | 0.047 |
| Achromatopsia (no color) | #939393 | 0.078 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #559DB0
#559DB0
oklch(65.6% 0.077 217)
- #BB816F
#BB816F
oklch(65.7% 0.077 38)
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 #559DB0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cadet Blue #5F9EA0 ΔE 0.026
- Greyblue #77A1B5 ΔE 0.040
- Dull Teal #5F9E8F ΔE 0.051
- Blue Grey #758DA3 ΔE 0.051
- Sea #3C9992 ΔE 0.052
- Silver Lake Blue #778DA9 ΔE 0.053
- Grey Teal #5E9B8A ΔE 0.055
- Bluegrey #85A3B2 ΔE 0.057
Use #559DB0 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.