RGB to CMYK Converter
To convert RGB to CMYK, divide each RGB value by 255, set K to 1 minus the largest of them, and compute C, M and Y from what is left. The result is an approximate starting value: for real print jobs, the printer’s color profile decides the exact ink percentages. Enter RGB or HEX below.
RGB to CMYK converter
The live converter needs JavaScript. Example: #1E90FF = rgb(30, 144, 255) = hsl(210, 100%, 56%) = cmyk(88%, 44%, 0%, 0%).
- HEX
– - RGB
– - HSL
– - CMYK
–
CMYK is approximate. For print, use your printer’s color profile.
The simple formula
| Step | What to do | Example: dodger blue |
|---|---|---|
| 1 | Divide R, G, B by 255 to get values from 0 to 1. | 0.118, 0.565, 1.0 |
| 2 | K = 1 − max(R′, G′, B′). | K = 0 |
| 3 | C = (1 − R′ − K) / (1 − K), same for M with G′ and Y with B′. | C 88%, M 44%, Y 0% |
| 4 | Pure black (0, 0, 0) is C 0, M 0, Y 0, K 100. | cmyk(88%, 44%, 0%, 0%) |
This is the standard textbook conversion. It assumes perfect inks on perfect paper and no color profile, so treat it as a guide. It also uses no more black than necessary, while real printing often replaces part of C, M and Y with black ink to save ink and dry faster.
What is the difference between RGB and CMYK?
RGB mixes light: red, green and blue light added together make white, as on a screen. CMYK mixes ink: cyan, magenta and yellow absorb light, and together they make a dark brown-black, so black ink (K) is added. Because they work so differently, some colors exist in one and not the other.
- Bright, saturated screen colors such as pure green #00FF00 or electric blue cannot be printed exactly with standard CMYK inks. They come out duller.
- Some CMYK colors are slightly outside what an sRGB screen can show.
- Paper matters: the same CMYK values look different on glossy coated paper and on uncoated or newsprint paper.
Why does my printed color look different?
The printed color depends on ink, paper, the printing press and the light you look at it in, while the screen color depends on your display and its brightness. Ask your printer which color profile they use (for example a FOGRA or GRACoL profile), convert in a design program with that profile, and order a proof for important colors.
| Color | HEX | CMYK (approx.) |
|---|---|---|
| Red | #FF0000 | 0, 100, 100, 0 |
| Lime green | #00FF00 | 100, 0, 100, 0 |
| Blue | #0000FF | 100, 100, 0, 0 |
| White | #FFFFFF | 0, 0, 0, 0 |
| Black | #000000 | 0, 0, 0, 100 |
| Mid gray | #808080 | 0, 0, 0, 50 |
| Dodger blue | #1E90FF | 88, 44, 0, 0 |
| Tomato | #FF6347 | 0, 61, 72, 0 |
| Gold | #FFD700 | 0, 16, 100, 0 |
| Rebecca purple | #663399 | 33, 67, 0, 40 |
| Teal | #008080 | 100, 0, 0, 50 |
| Saddle brown | #8B4513 | 0, 50, 86, 45 |
HSL rounded to whole numbers. CMYK from the simple formula below, without a color profile.
Frequently asked questions
How do I convert RGB to CMYK?
Divide R, G and B by 255. K is 1 minus the largest of the three. Then C = (1 − R − K) / (1 − K), and the same for M with G and Y with B. Multiply by 100 for percentages. The converter above does it instantly.
Is this CMYK value accurate for print?
It is approximate. The simple formula ignores the printer’s ink, paper and color profile. For brand colors or large print runs, convert with your printer’s profile in a design program and check a printed proof.
What is the difference between RGB and CMYK?
RGB is additive color for screens: red, green and blue light combine to make white. CMYK is subtractive color for printing: cyan, magenta, yellow and black inks absorb light. A file for print is usually prepared in CMYK, a file for screens in RGB.
Why does my printed color look different from the screen?
Screens emit light and can show brighter, more saturated colors than ink on paper. The printer’s ink, the paper type and the room light also change the result. Bright greens, blues and oranges change the most.
What is K in CMYK?
K stands for key, which in printing means the black plate. Black ink is added because mixing cyan, magenta and yellow gives a muddy dark color, uses a lot of ink and makes text less sharp.
How do I get CMYK values from an image?
Open the image in the color picker on the home page and click the color. The result shows its CMYK estimate next to the HEX, RGB and HSL codes.
Last updated: October 15, 2026