Tool
What the CMYK Converter does
CMYK Converter: converts CMYK, HEX and RGB from Pick a colour.
This converter reads Pick a colour and produces CMYK, HEX and RGB. Adjust anything and the figures re-derive on the spot.
Most people who open the CMYK Converter are developers translating a value into CSS. The same colour is written half a dozen ways, and design tools rarely agree on which.
The page holds your values in memory and forgets them the moment you close it.
Each field is explained further down, along with the method and a worked example that uses the default values.
What do the CMYK Converter fields mean?
The CMYK Converter uses 1 input. The page opens in a usable state: real values in, real answer out, ready to edit.
| Field | What to enter | Default |
|---|---|---|
| Pick a colour | optional | #2563eb |
How does the CMYK Converter work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same conversion.
If something is off you are told which field, not given a generic failure.
What a typical run looks like
You provide: Pick a colour
What happens: the file is read into memory by your browser, processed locally, and offered back as a download. It is never uploaded.
You get back: a new file plus a brief account of what happened to it, shown in the panel.
How long this takes is a property of your computer, not of our infrastructure, and file size is bounded by browser memory.
CMYK and why it is not RGB
CMYK is subtractive: ink absorbs light, so adding all four channels approaches black. RGB is additive: light is emitted, so adding all three approaches white. They are not merely different notations for the same colours. They describe genuinely different gamuts.
| Channels | Cyan, Magenta, Yellow, Key (black) | 0 to 100% each |
|---|---|---|
| Model | Subtractive: ink on paper | more ink = darker |
| Gamut | Smaller than sRGB | cannot reproduce vivid RGB greens and blues |
| Use | Print production | never for screen display |
Worth knowing
- The K channel exists because mixing C, M and Y at 100% gives a muddy brown rather than black, and because pure black ink is far cheaper than three-colour overprint.
- Bright screen colours (saturated cyan, vivid orange, electric green) are outside the CMYK gamut and will print noticeably duller. This is physics, not a conversion error.
- An accurate conversion needs an ICC profile for the specific paper and press. A formula-based conversion is an approximation and should not be used for final artwork.
- Total ink coverage is usually capped around 240 to 300% depending on the press; exceeding it causes smudging and drying problems.
How to use it
- Set Pick a colour.
- Skip the submit button; there is not one. Editing is enough.
- Check CMYK, HEX, RGB, HSL and HSV on the right.
- Copy Link when you want to return to this exact configuration; Print when someone needs it on paper.
What this tool does not do
- Colours render differently across displays; the values are exact but the appearance is not guaranteed.
- Conversions between colour spaces with different gamuts are approximate at the edges.
- There is no history: reload the page and the previous run is gone.
Frequently asked questions
Pick a colour, nothing else. Every box already holds a working value, so you can change one value at a time and watch how the result responds.
No. Your browser is doing the computing, so we could not see the values even if we wanted to.
No charge. Everything on the page is available without signing in.
The formula is shown above precisely so you do not have to take the accuracy on trust.