Instantly convert CMYK color values to RGB and HEX — or RGB back to CMYK. Live color preview updates as you adjust the sliders. Essential for designers working across print and digital. Free and private.
Understanding the difference between CMYK and RGB is essential for anyone who designs for both print and digital media.
CMYK (Cyan, Magenta, Yellow, Key/Black) is the color model used by printers. Colors are created by mixing ink — adding more ink makes the color darker (subtractive color).
RGB (Red, Green, Blue) is the color model used by monitors, phones, and TVs. Colors are created by combining light — adding more light makes it brighter (additive color).
Designers create visuals on screen (RGB) but send files to print (CMYK). Converting correctly ensures the printed colors match what you see on screen as closely as possible.
RGB can display brighter, more saturated colors than CMYK can print. Very bright neon RGB colors like pure #FF0000 red may look slightly muted in print. Always check a print proof.
K stands for Key (black). Pure black could technically be made from 100% C+M+Y, but this uses too much ink and produces muddy results. A dedicated black ink gives sharper, cleaner results.
HEX colors like #FF5733 are just RGB expressed in hexadecimal. FF=255 Red, 57=87 Green, 33=51 Blue. HEX is used in CSS, web design, and digital graphics tools.
R = 255 × (1 − C/100) × (1 − K/100). Apply same formula for G using M, and B using Y. All inputs are percentages 0–100.
First find K = 1 − max(R,G,B)/255. Then C = (1−R/255−K)/(1−K). Apply same formula for M using G, and Y using B.
Convert each RGB value (0–255) to 2-digit hexadecimal. R=255, G=87, B=51 → #FF5733. Used in CSS, HTML, and web design tools.
R = 255 × (1 − C/100) × (1 − K/100). G = 255 × (1 − M/100) × (1 − K/100). B = 255 × (1 − Y/100) × (1 − K/100). Where C, M, Y, K are percentages from 0 to 100.
CMYK stands for Cyan, Magenta, Yellow, and Key (Black). It is the color model used in color printing. The K stands for Key because in printing, the black plate is the "key" plate that other color plates are aligned to.
Screens use RGB (additive — combining light), while printers use CMYK (subtractive — combining ink). The two color spaces overlap but are not identical. Some vibrant screen colors cannot be reproduced in print. This is called being "out of gamut".
Use RGB for anything displayed on a screen — websites, social media, digital ads, apps, and video. Use CMYK for anything printed — business cards, brochures, posters, and packaging. When in doubt about what your printer expects, ask them — most professional print services require CMYK PDF files.
A HEX color code (like #FF5733) is an RGB color expressed in hexadecimal notation. The first two characters are Red, the next two are Green, and the last two are Blue — each ranging from 00 (0) to FF (255). HEX colors are used in CSS, HTML, and most digital design tools.
Mathematically yes — both represent pure black. However in print, pure black from RGB converts to rich black (CMYK mixed), while CMYK (0,0,0,100) is true black ink only. For text and fine lines in print, always use CMYK (0,0,0,100) to avoid registration issues.
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