How to use the hex to cmyk converter
- Enter your hex color code in the input field. You can include the
#prefix or leave it off. - The converter immediately calculates the cyan, magenta, yellow and key percentages.
- Copy the individual values or the combined CMYK string for use in your design software.
- Remember that this is a screen approximation: always verify against a printed proof or ICC profile for critical work.
How the hex to cmyk conversion works
A hex code represents red, green and blue light on a screen, while CMYK represents ink on paper. The conversion first normalizes the RGB channels to a 0 to 1 range, then derives the key (black) component as the inverse of the brightest channel.
The formulas are:
K = 1 - max(R', G', B')C = (1 - R' - K) / (1 - K)M = (1 - G' - K) / (1 - K)Y = (1 - B' - K) / (1 - K)
For example, the hex code #3498db gives R=52, G=152, B=219. Normalized: R'=0.204, G'=0.596, B'=0.859. The maximum is 0.859, so K = 1 - 0.859 = 0.141 (14%). Then C = (1 - 0.204 - 0.141) / 0.859 = 0.762 (76%), M = (1 - 0.596 - 0.141) / 0.859 = 0.306 (31%), Y = (1 - 0.859 - 0.141) / 0.859 = 0 (0%).
Common hex colors and their CMYK values
This table shows the approximate CMYK equivalents for frequently used hex colors. Values are rounded to whole percentages.
| Color name | Hex code | C | M | Y | K |
|---|---|---|---|---|---|
| Black | #000000 | 0% | 0% | 0% | 100% |
| White | #FFFFFF | 0% | 0% | 0% | 0% |
| Red | #FF0000 | 0% | 100% | 100% | 0% |
| Green | #00FF00 | 100% | 0% | 100% | 0% |
| Blue | #0000FF | 100% | 100% | 0% | 0% |
| Yellow | #FFFF00 | 0% | 0% | 100% | 0% |
| Cyan | #00FFFF | 100% | 0% | 0% | 0% |
| Magenta | #FF00FF | 0% | 100% | 0% | 0% |
Screen approximation versus professional color management
This hex to cmyk converter uses the standard mathematical formula to translate additive screen colors into subtractive ink percentages. It provides a useful starting point, but it does not account for ink characteristics, paper stock or specific press profiles.
Professional print workflows rely on ICC color profiles such as U.S. Web Coated (SWOP) v2 or Fogra39. These profiles map colors based on measured ink behavior rather than pure math. If you need an exact match for brand guidelines, convert your hex color to cmyk using your design application's assigned profile, or consult a printed swatch book.
For matching branded spot colors, you may also want to explore hex to pantone lookups or convert back from print using a cmyk to hex tool.
Accepted hex formats
The input field accepts several common ways designers write hex codes. You can type the hash symbol or omit it, and the converter handles both cases automatically.
- Six-digit with hash:
#3498db - Six-digit without hash:
3498db - Three-digit shorthand:
#f0a(expanded to#ff00aa) - Uppercase or lowercase:
#FF00AAand#ff00aaproduce identical results
Whitespace around the value is trimmed before parsing. Invalid characters or incorrect lengths will return a clear error message.
When to use CMYK instead of hex
Hex codes are designed for screens where colors are created by emitting red, green and blue light. CMYK is designed for physical printing where cyan, magenta, yellow and black inks absorb light reflected off paper.
Use CMYK values when preparing files for offset printing, digital presses, business cards, brochures or packaging. Use hex codes for websites, mobile apps and on-screen presentations. If you need to move between color spaces frequently, pairing this tool with a hex to rgb converter helps keep all three representations consistent across your project.
Worked examples
| Example | Input | Result |
|---|---|---|
| Bright blue | HEX color code: #3498db | Cyan (C): 76%; Magenta (M): 31%; Yellow (Y): 0%; Key (K): 14%; CMYK string: 76, 31, 0, 14 |
| Pure red | HEX color code: FF0000 | Cyan (C): 0%; Magenta (M): 100%; Yellow (Y): 100%; Key (K): 0%; CMYK string: 0, 100, 100, 0 |
| Short white | HEX color code: #fff | Cyan (C): 0%; Magenta (M): 0%; Yellow (Y): 0%; Key (K): 0%; CMYK string: 0, 0, 0, 0 |
| Dark gray | HEX color code: 333 | Cyan (C): 0%; Magenta (M): 0%; Yellow (Y): 0%; Key (K): 80%; CMYK string: 0, 0, 0, 80 |
FAQ
Is this hex to cmyk conversion accurate for professional printing?
It uses the standard mathematical formula to convert screen colors to ink percentages. This gives a close screen approximation, but professional printing requires ICC color profiles calibrated to specific inks and paper types.
Can I enter a hex code without the # symbol?
Yes. The converter strips the hash if present and accepts plain six-character or three-character strings like 3498db or f0a.
Why do my printed colors look different from the hex code on screen?
Screens emit light using RGB, while printers reflect light using CMYK inks. Some bright screen colors fall outside the printable gamut of standard inks, causing a visible shift.
What does the K stand for in CMYK?
K stands for Key, which refers to the black ink plate used to align the other color plates in offset printing. It avoids confusion with Blue in RGB.
Does this tool support 8-digit hex codes with alpha transparency?
No. CMYK printing does not use an alpha channel in the same way screens do. Enter a standard 3-digit or 6-digit hex color code.
How do I convert the result back to a hex code?
You can use a cmyk to hex converter to reverse the process, keeping in mind that round-trip conversions may shift slightly due to rounding.