About

CMYK (Cyan, Magenta, Yellow, Key/Black) is the subtractive color model used in commercial printing. HEX codes are the standard for digital screens and CSS. Mismatched conversion between these two systems causes printed output to diverge from on-screen previews - a costly error in branding, packaging, and any print-to-web workflow. This tool computes R, G, B channels from your CMYK percentages using the ICC-standard formula, then encodes the result as a six-digit hexadecimal string. It does not apply ICC color profiles or gamut mapping. CMYK color spaces are device-dependent; the conversion here assumes a normalized model where each channel ranges from 0 to 100%.

Note: true CMYK-to-sRGB fidelity requires hardware-calibrated ICC profiles. This tool provides the mathematical conversion, which is sufficient for web design mockups and general reference. For press-critical work, verify output against a Pantone bridge or spectrophotometer reading.

Formulas

The CMYK-to-RGB conversion uses a normalized subtractive model. Each CMYK channel is expressed as a percentage from 0 to 100. The Key (black) channel attenuates all three RGB components uniformly.

R = 255 × (1 − C100) × (1 − K100)

G = 255 × (1 − M100) × (1 − K100)

B = 255 × (1 − Y100) × (1 − K100)

Where C = Cyan (0 - 100%), M = Magenta (0 - 100%), Y = Yellow (0 - 100%), K = Key/Black (0 - 100%). Each resulting RGB value is rounded to the nearest integer and clamped to [0, 255]. The HEX code is then formed by converting each channel to a two-digit base-16 string: HEX = concat(#, R₁₆, G₁₆, B₁₆).

Reference Data

Color Name	C	M	Y	K	HEX	RGB
Pure Black	0	0	0	100	#000000	0, 0, 0
Pure White	0	0	0	0	#FFFFFF	255, 255, 255
Pure Cyan	100	0	0	0	#00FFFF	0, 255, 255
Pure Magenta	0	100	0	0	#FF00FF	255, 0, 255
Pure Yellow	0	0	100	0	#FFFF00	255, 255, 0
Rich Black (FOGRA)	60	40	40	100	#000000	0, 0, 0
Process Red	0	100	100	0	#FF0000	255, 0, 0
Process Green	100	0	100	0	#00FF00	0, 255, 0
Process Blue	100	100	0	0	#0000FF	0, 0, 255
Warm Gray	0	5	10	30	#B3A9A1	179, 169, 161
Cool Gray	10	5	0	30	#A1A9B3	161, 169, 179
Sky Blue	50	10	0	5	#79DAF2	121, 218, 242
Forest Green	80	10	100	30	#24A100	36, 161, 0
Coral	0	50	50	0	#FF8080	255, 128, 128
Navy	100	80	0	45	#001C8C	0, 28, 140
Burnt Orange	0	60	100	10	#E65C00	230, 92, 0
Lavender	15	25	0	5	#CEB6F2	206, 182, 242
Olive	20	0	80	40	#7A991E	122, 153, 30
Teal	80	0	30	20	#29CC8F	41, 204, 143
Skin Tone (Light)	0	15	25	5	#F2CEB6	242, 206, 182
Chocolate	10	60	80	50	#733319	115, 51, 25
50% Gray	0	0	0	50	#808080	128, 128, 128

Frequently Asked Questions

CMYK is device-dependent. The mathematical conversion assumes an idealized model. Real printers use ICC profiles that account for ink absorption, paper whiteness, and dot gain. The HEX output here matches the standard normalized formula, but a Pantone bridge or proofing software should be consulted for press-critical color matching.

When K = 100, the factor (1 − K/100) becomes 0, zeroing out all RGB channels. The result is always #000000 (pure black), regardless of C, M, or Y. In print, a "rich black" (e.g., C60 M40 Y40 K100) produces a deeper black than K-only, but the mathematical RGB equivalent is still zero.

For web design purposes the conversion is exact. CSS operates in sRGB, and this tool outputs the correct sRGB HEX code from the standard CMYK formula. The limitation is only relevant when matching physical print output, where ICC profiles introduce non-linear corrections.

No. This tool clamps all inputs to the valid range of 0 to 100. In professional printing, total area coverage (TAC) - the sum of C + M + Y + K - is typically limited to 300 - 340% to prevent ink bleeding. This converter does not enforce TAC limits as it targets screen color output.

The CMYK-to-RGB mapping is surjective, not injective. Multiple CMYK combinations collapse to the same RGB triplet after rounding. For example, C0 M0 Y0 K50 and C1 M0 Y0 K50 both round to #808080 because the 1% cyan shift produces a sub-unit RGB difference (< 0.5) that rounds away.

No. ICC profile-based conversion requires lookup tables (CLUTs) and interpolation across 3D color volumes, which are hardware- and vendor-specific. This tool uses the device-independent mathematical formula. For profile-aware conversion, use Adobe Photoshop or a dedicated color management system with embedded profile data.