Result
This page has no server side at all. The table you paste is parsed by JavaScript inside your own browser, the chart is drawn on a canvas element on your machine, and the export file is assembled locally. Nothing is uploaded, stored or written to any log. You can disconnect from the network after the page has loaded and everything will still work — which is the simplest way to verify the claim yourself.
Facts and limits of this method
| Intermediate step | CMYK is first converted to RGB, then to HEX |
|---|---|
| Input range | C, M, Y, K from 0% to 100% |
| Result format | #RRGGBB — six hexadecimal digits |
| Result case | Letters A–F are output uppercase |
When it misleads you
- This is a mathematical approximation, not the output of an actual printer's color profile — a real print may look different due to inks, paper and equipment.
- CMYK is a subtractive model for print, HEX/RGB is additive for screens; converting between them always loses some accuracy.
- The formula assumes the simplest ink-mixing scheme with no ICC profile — for color-critical print jobs use dedicated software.
- Rounding of percentages and byte values can shift the resulting shade slightly if you convert back and forth repeatedly.
How it is calculated
The C, M, Y and K percentages are converted to fractions from 0 to 1 by dividing by 100.
For each of R, G, B, the product (1 − color fraction) × (1 − black fraction) is computed, then multiplied by 255 and rounded to a whole number.
The resulting R, G, B numbers are converted to two-digit hexadecimal pairs.
The three pairs are joined in order with a leading "#" — producing a 6-digit HEX code.
Questions and answers
Why doesn't the on-screen color match what actually prints?
A screen shows light (RGB/HEX), while paper shows reflected light after ink is applied (CMYK); an exact match needs a profile for the specific printer and paper.
Can I use the result as a final design color?
Yes, as a guideline for interfaces and digital layouts — it's accurate enough for most everyday tasks.
Why does the code differ slightly after HEX→CMYK→HEX round-tripping?
Rounding of CMYK percentages and RGB byte values accumulates a small error at each step.
Is my data sent anywhere?
No, the whole calculation runs in your browser.