About the CMYK to HSV Converter
Artwork prepared for press stores colour as ink coverage, but the moment you open it in a picker to adjust something you are handed hue, saturation and value sliders instead. This converter bridges the two. Each quadruple is expanded to sRGB by scaling every channel by one minus its ink and then again by one minus the key, and the resulting triple is measured as an angle on the colour wheel plus two percentages.
Two properties of the arithmetic are worth carrying in your head. Key behaves as a straight brightness cap, so raising it on its own lowers the value while leaving hue and saturation untouched, which makes it the quickest way to darken a mix without changing its character. And when cyan, magenta and yellow are all equal the result is a neutral grey, reported with a hue of 0 and a saturation of 0 because no channel dominates.
Input accepts the cmyk() wrapper, bare comma separated numbers, or space separated ones, with percent signs optional and one colour on each line. Anything outside 0 to 100 raises an error rather than being silently clamped, so a mistyped 450 cannot become full ink behind your back. The opposite direction is at HSV to CMYK, and the Color Converter prints HEX, HSL and Lab in one pass if you need more than one notation.
How to use
- Paste CMYK quadruples, one colour per line.
- Press Convert to read the hsv() triples.
- Enter the hue in degrees and the two percentages in your picker.
Common questions
- What ranges do the three outputs use?
- Hue runs from 0 to 360 degrees while saturation and value are percentages from 0 to 100.
- Why does adding black change only one of the three numbers?
- The key ink scales all three channels equally, which lowers value while the hue angle and the saturation stay where they were.
- Is this conversion colour managed?
- No, it uses the plain subtractive formula with no ICC profile, so a proofed press result will differ slightly.
- What does an equal mix of cyan, magenta and yellow give?
- A neutral grey, which comes back with zero saturation and a hue of zero.