CMYK to Hex Converter
Convert CMYK print percentages back into a 6-digit hex color code for screens, CSS, and design tools — with rounding notes explained.
How CMYK to Hex Conversion Works
Each CMY channel combines with the black (K) channel to produce one RGB value: full strength (255) is reduced by both the channel's own percentage and the black percentage. The three resulting RGB values are rounded to whole numbers and converted to hex the same way an RGB to hex conversion works.
CMYK to Hex Example, Step by Step
cmyk(0%, 100%, 100%, 0%) = #FF0000
cmyk(0%, 100%, 100%, 0%) = #FF0000
R = 255 x (1-0) x (1-0) = 255 -> FF G = 255 x (1-1) x (1-0) = 0 -> 00 B = 255 x (1-1) x (1-0) = 0 -> 00 Combine: FF + 00 + 00 = FF0000
| Step | Description | Result |
|---|---|---|
| Compute red | 255 x (1-C) x (1-K) | 255 -> FF |
| Compute green | 255 x (1-M) x (1-K) | 0 -> 00 |
| Compute blue | 255 x (1-Y) x (1-K) | 0 -> 00 |
| Combine with # prefix | join all three pairs | #FF0000 |
This is a clean round-number case, so it converts back to hex exactly. Values with less round CMYK percentages can drift by 1 unit in a channel due to rounding — see the FAQ below.
Common Mistakes With CMYK to Hex
- Expecting a hex value converted to CMYK and back to always match exactly — rounding at the CMYK stage can shift a channel by 1.
- Forgetting the black (K) channel applies to all three RGB calculations, not just one.
- Entering CMYK percentages above 100% or below 0%, which have no valid ink coverage meaning.
Frequently Asked Questions
How do you convert CMYK to hex?
Convert each CMY channel to RGB using R = 255 x (1-C) x (1-K), and the same pattern for G with magenta and B with yellow. Round each result to the nearest whole number, then convert to 2-digit hex pairs.
What's the hex value of cmyk(0%, 100%, 100%, 0%)?
#FF0000 — pure red, since 0% cyan and 0% black leave the red channel at full strength while magenta and yellow fully remove green and blue.
What format does this tool accept for CMYK input?
Either plain comma-separated percentages (84%, 58%, 0%, 8%) or a full cmyk() function string (cmyk(84%, 58%, 0%, 8%)) — both work the same.
Why might cmyk-to-hex not give back the exact original hex?
CMYK percentages round to whole numbers, so converting hex to CMYK and back to hex can drift by 1 unit in a channel. For example, #2563EB converts to cmyk(84%, 58%, 0%, 8%), and converting that back gives #2663EB — a 1-digit shift caused by the intermediate rounding.
What CMYK values produce pure black or white?
cmyk(0%, 0%, 0%, 100%) gives #000000 (black), and cmyk(0%, 0%, 0%, 0%) gives #FFFFFF (white).