What is CMYK?
CMYK is a subtractive color model used in color printing, where cyan, magenta, yellow, and black inks are combined in varying amounts to create a wide spectrum of colors on paper and other physical media.
Quick Facts
| Full Name | Cyan Magenta Yellow Key (Black) |
|---|---|
| Created | 1906 (Eagle Printing Ink Company) |
| Specification | Official Specification |
How It Works
CMYK is the standard color model for print production, working on the principle of subtractive color mixing. Unlike RGB which adds light to create colors (additive), CMYK subtracts light from white paper by absorbing certain wavelengths. The 'K' stands for 'Key' (black), used instead of 'B' to avoid confusion with blue. Black ink is added separately because combining CMY inks produces a muddy brown rather than true black, and using black ink is more economical for text and dark areas. CMYK values are expressed as percentages from 0% to 100% for each color channel. The color gamut of CMYK is smaller than RGB, which is why colors may appear less vibrant in print than on screen. Professional designers typically work in RGB during design and convert to CMYK before printing, being mindful of colors that fall outside the CMYK gamut.
Key Characteristics
- Subtractive color model - removes light from white surface
- Four color channels: Cyan, Magenta, Yellow, and Black (Key)
- Values expressed as percentages (0-100%)
- Smaller color gamut than RGB (some colors cannot be printed)
- Black added separately for true blacks and economy
- Standard for commercial printing (offset, digital press)
Common Use Cases
- Commercial printing (magazines, brochures, packaging)
- Business cards and stationery design
- Product packaging and labels
- Book and publication printing
- Large format printing (posters, banners)
Example
Loading code...Frequently Asked Questions
Why does CMYK use black (K) separately instead of mixing CMY?
Mixing cyan, magenta, and yellow inks produces a muddy brown rather than true black due to ink impurities. Adding black (K for 'Key') separately provides deeper, crisper blacks, reduces ink consumption, improves text sharpness, and lowers printing costs since black ink is cheaper than combining three colors.
Why do colors look different on screen versus when printed?
Screens use RGB (additive color with light), while printers use CMYK (subtractive color with ink). CMYK has a smaller color gamut than RGB, so vibrant screen colors often appear duller in print. Additionally, paper type, ink quality, and printing conditions affect final color appearance.
When should I use CMYK versus RGB?
Use CMYK for anything that will be printed physically: brochures, business cards, magazines, packaging. Use RGB for digital displays: websites, apps, social media, presentations. Always convert RGB designs to CMYK before sending to print to avoid unexpected color shifts.
What is rich black and when should I use it?
Rich black combines CMYK values (typically C60 M40 Y40 K100) instead of using 100% black alone. It produces a deeper, more saturated black ideal for large solid areas. Use rich black for backgrounds and large graphics, but use pure black (K100) for small text to avoid registration issues.
How do I convert RGB colors to CMYK accurately?
Use professional design software like Adobe Photoshop, Illustrator, or free tools like GIMP. These applications use ICC color profiles for conversion. Be aware that some RGB colors fall outside CMYK gamut and will be approximated. Always soft-proof your design in CMYK mode before printing.