About

Color conversion is the bridge between the physical and digital worlds. This tool facilitates the translation of Subtractive Color Models (CMYK), used in offset printing and physical pigments, to Additive Color Models (RGB), used in illuminated screens and web design. Accurate conversion is critical for maintaining brand consistency across varied media formats.

Unlike simple calculators, this engine employs industry-standard algorithms to map the 0-100 Cyan, Magenta, Yellow, and Key (Black) values to the 0-255 Red, Green, and Blue integers. It includes a built-in gamut warning system, alerting designers when a screen-based color (typically high-saturation RGB) cannot be physically reproduced by standard four-color process printing without significant dulling.

Formulas

The mathematical transformation normalizes inputs to a [0, 1] range before scaling to the target bit depth.

Step 1: Normalize CMYK

Where C, M, Y, K ∈ [0, 100]

c = C / 100m = M / 100y = Y / 100k = K / 100

Step 2: Calculate RGB

Resulting R, G, B values are rounded to the nearest integer.

R = 255 × (1 − c) × (1 − k)G = 255 × (1 − m) × (1 − k)B = 255 × (1 − y) × (1 − k)

Reference Data

Color Name	CMYK (Print)	RGB (Screen)	HEX	Usage Context
Rich Black	60, 40, 40, 100	0, 0, 0	#000000	High-density backgrounds
Standard Black	0, 0, 0, 100	28, 28, 28	#1C1C1C	Text, Fine lines
Registration Black	100, 100, 100, 100	0, 0, 0	#000000	Printer alignment marks only
Pantone 185 C (Red)	0, 93, 79, 0	239, 51, 64	#EF3340	Brand identities
Pantone 286 C (Blue)	100, 75, 0, 0	0, 50, 160	#0032A0	Corporate logos
Cool Gray 11	44, 34, 22, 77	83, 86, 90	#53565A	Neutral UI elements
Gold (Metallic sim)	0, 20, 100, 20	204, 163, 0	#CCA300	Luxury accents

Frequently Asked Questions

This is due to the "Out of Gamut" phenomenon. RGB (screens) emits light and can produce neon, highly saturated brights. CMYK (print) reflects light using ink and has a much narrower range of reproduceable colors. When you convert a bright neon green from RGB to CMYK, the software clamps it to the nearest printable duller green.

Standard Black uses only black ink (0, 0, 0, 100). It is cheap and sharp, ideal for text. Rich Black adds percentages of Cyan, Magenta, and Yellow (e.g., 60, 40, 40, 100) to create a deeper, darker tone for large backgrounds. Never use Rich Black for small text as minor alignment shifts (misregistration) will make the text blurry.

Mathematically, yes. However, HEX is strictly an RGB format (Screen). A HEX code converted to CMYK and back to HEX might shift slightly due to rounding errors, as CMYK uses 0-100 percentages while RGB uses 0-255 integers.

Our tool uses the standard GCR (Gray Component Replacement) approach where the maximum common value of CMY is pulled into the K channel to save colored ink and improve neutral tones.