🖨️ CMYK to RGB and HEX Converter

By ToolNimba Design Team · Updated 2026-06-19

CMYK (each 0 to 100)

RGB

HEX

Edit CMYK, RGB or HEX, or use the picker. The others update live. CMYK is approximate on a screen.

This converter turns CMYK values into RGB and hex, and works in reverse too. Type the cyan, magenta, yellow and key (black) percentages, each from 0 to 100, and you instantly get the matching RGB triple and hex code with a live swatch. You can also edit the RGB or hex side, or use the color picker, and the CMYK values update to match. It is handy when you are moving a print color into a screen design, or checking roughly how a screen color would break down for print.

What is the CMYK to RGB Converter?

CMYK is the four-ink color model used in printing: cyan, magenta, yellow and key, where key means black. It is a subtractive model, meaning each ink absorbs (subtracts) some of the light hitting the paper. Pile on all the inks and you approach black, which is why printers add a dedicated black ink (the K) instead of relying on heavy cyan, magenta and yellow alone. RGB, by contrast, is the additive model your screen uses: red, green and blue light are added together, and at full strength they make white.

Because the two models are built on opposite ideas, converting between them is always an approximation. The simple math this tool uses maps the percentages directly: red is 255 times one minus cyan, scaled down by one minus the key value, and the same pattern gives green from magenta and blue from yellow. It is the standard formula you will see in most design references, and it is exact and reversible for the arithmetic itself, but it does not know anything about real inks, paper, or how your monitor is calibrated.

That is the key caveat. A true print workflow uses ICC color profiles that describe a specific printer, ink set and paper, so the same CMYK numbers can look different on different presses. This converter gives you a fast, consistent screen approximation, perfect for picking a color, sanity checking a value, or starting a design. For a final print job, always trust a proof and the profile your print shop provides rather than the on-screen swatch.

When to use it

Taking a CMYK color from a print brand guide and getting a usable RGB or hex value for a website or app.
Roughly converting a screen color to CMYK to see how it might break down into print inks.
Checking whether a chosen color leans heavily on black ink, which often prints cleaner than a mix of three inks.
Translating a logo color between a print spec and a digital style sheet so both look as close as possible.

How to use the CMYK to RGB Converter

Enter the cyan, magenta, yellow and key (black) percentages, each from 0 to 100.
Read off the matching RGB value and hex code, and check the live swatch.
To go the other way, type an RGB value or a hex code, or use the color picker, and the CMYK fields update.
Use the copy buttons to grab the RGB, hex or CMYK string for your design file.

Formula & method

CMYK to RGB: R = 255 × (1 − C) × (1 − K), G = 255 × (1 − M) × (1 − K), B = 255 × (1 − Y) × (1 − K), where C, M, Y, K are the percentages divided by 100. RGB to CMYK: scale R, G, B to the range 0 to 1, then K = 1 − max(R, G, B), C = (1 − R − K) ÷ (1 − K), M = (1 − G − K) ÷ (1 − K), Y = (1 − B − K) ÷ (1 − K). If K = 1 (pure black) then C, M and Y are all 0.

Worked examples

Convert CMYK(0, 100, 100, 0), a pure red mix, to RGB and hex.

C = 0, M = 1, Y = 1, K = 0 after dividing by 100
R = 255 × (1 − 0) × (1 − 0) = 255
G = 255 × (1 − 1) × (1 − 0) = 0
B = 255 × (1 − 1) × (1 − 0) = 0
Combine (255, 0, 0) into hex

Result: RGB is rgb(255, 0, 0), hex is #FF0000, a pure red

Convert the orange rgb(255, 128, 0) back to CMYK.

Scale to 0 to 1: R = 1, G = 0.502, B = 0
K = 1 − max(1, 0.502, 0) = 1 − 1 = 0
C = (1 − 1 − 0) ÷ (1 − 0) = 0
M = (1 − 0.502 − 0) ÷ 1 = 0.498, about 50%
Y = (1 − 0 − 0) ÷ 1 = 1, about 100%

Result: CMYK is about (0%, 50%, 100%, 0%)

Common colors in CMYK with their RGB and hex equivalents

Color	CMYK	RGB	Hex
Red	0, 100, 100, 0	rgb(255, 0, 0)	#FF0000
Green	100, 0, 100, 0	rgb(0, 255, 0)	#00FF00
Blue	100, 100, 0, 0	rgb(0, 0, 255)	#0000FF
Yellow	0, 0, 100, 0	rgb(255, 255, 0)	#FFFF00
White	0, 0, 0, 0	rgb(255, 255, 255)	#FFFFFF
Black	0, 0, 0, 100	rgb(0, 0, 0)	#000000

What each CMYK channel means

Channel	Letter	Role
Cyan	C	Absorbs red light, a blue-green ink
Magenta	M	Absorbs green light, a pink-red ink
Yellow	Y	Absorbs blue light
Key	K	Black ink, for depth and clean text

Common mistakes to avoid

Expecting the screen color to match the print exactly. The simple formula ignores real inks, paper and monitor calibration. The on-screen swatch is an approximation only. For a final print job, rely on a proof and the ICC profile your print shop supplies.
Entering CMYK values above 100 or below 0. Each CMYK channel is a percentage from 0 to 100. Values outside that range are clamped, so a typo like 120 will be treated as 100 rather than producing a meaningful color.
Confusing K with a fifth color. K stands for key, which is black. It is not a separate hue but the black ink used to add depth and keep text crisp without overloading the other three inks.
Assuming the conversion is perfectly round-trip stable. CMYK percentages are whole numbers here, so converting RGB to CMYK and back can shift a channel by one unit due to rounding. The difference is invisible but it explains tiny mismatches.

Glossary

CMYK: The four-ink subtractive color model used in printing: cyan, magenta, yellow and key (black), each given as a percentage.
RGB: The additive color model used by screens, describing a color by its red, green and blue light, each from 0 to 255.
Key (K): The black channel in CMYK, used to add depth and print sharp text instead of mixing three inks for dark areas.
Subtractive color: A model where inks or pigments absorb light, so adding more colorant moves the result toward black.
ICC profile: A data file that describes how a specific device reproduces color, used to convert accurately between CMYK and RGB.

Frequently asked questions

How do I convert CMYK to RGB?

Use the formula R = 255 × (1 − C) × (1 − K), G = 255 × (1 − M) × (1 − K), and B = 255 × (1 − Y) × (1 − K), where C, M, Y and K are the percentages divided by 100. This converter applies it automatically when you type the four CMYK values.

Can I convert RGB back to CMYK here?

Yes. Type an RGB value or a hex code, or use the color picker, and the CMYK fields update. It first works out K as one minus the largest of the scaled red, green and blue, then derives cyan, magenta and yellow from the rest.

Why does my CMYK color look different when printed?

The math here is a generic screen approximation that ignores real inks, paper and monitor calibration. Actual printing uses ICC color profiles tied to a specific press, so the same CMYK numbers can print differently. Always check a physical proof.

What does the K in CMYK stand for?

K stands for key, which is the black ink. It is used because layering cyan, magenta and yellow to make black wastes ink and looks muddy, while a dedicated black gives deeper darks and crisper text.

Is CMYK to RGB conversion exact?

The arithmetic is exact and reversible, but the color match is not. RGB can display vivid colors that no ink set can reproduce, and CMYK can describe ink mixes that no screen shows perfectly, so any conversion between them is an approximation.

Why are some bright screen colors hard to match in CMYK?

Screens emit light and can hit very saturated reds, greens and blues. Printing inks reflect light and cover a smaller range, called a gamut, so the most vivid RGB colors fall outside what CMYK inks can print and get pulled toward the nearest printable shade.