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RGB to CMYK Converter

Turn RGB screen colors into CMYK ink percentages for print, with a live swatch.

Paste rgb(), bare values, or a hex code. Everything converts in your browser.

CMYK result
0%
Cyan
73%
Magenta
82%
Yellow
11%
Key (black)
CMYKcmyk(0%, 73%, 82%, 11%)
RGBrgb(226, 61, 40)
HEX#e23d28
Decimals

CMYK here is a standard formula approximation. Printed color depends on the press profile, ink, and paper, so treat these percentages as a starting point.

How to convert RGB to CMYK online

  1. Enter your color

    Paste an rgb() value, three 0 to 255 numbers, or a hex code, or drag the red, green, and blue sliders.

  2. Read the CMYK values

    The cyan, magenta, yellow, and key percentages update instantly, alongside a live swatch of the color.

  3. Copy the result

    Copy the full cmyk() string, or the matching RGB and HEX values, with one click.

Why use this tool

Converts as you type

CMYK percentages, the swatch, and the copyable strings all update instantly with every slider move or paste.

Accepts RGB, hex, and bare values

Paste rgb(226, 61, 40), 226 61 40, #e23d28, or shorthand hex; out-of-range channels are clamped to 0 to 255.

Per-ink breakdown

Each of the four inks gets its own card with a percentage readout and a proportional ink bar, at 0, 1, or 2 decimal places.

Handles the edge cases

Pure black converts cleanly to 100% key with zero colored ink, and pure white to all zeros, with no broken output.

Runs entirely in your browser

Colors are converted on your device; nothing is uploaded and no signup is needed.

About this tool

This tool converts RGB screen colors into CMYK ink percentages. RGB describes color as light (red, green, and blue from 0 to 255), which is how screens work. CMYK describes color as ink coverage (cyan, magenta, yellow, and key, meaning black, from 0 to 100 percent), which is how printers work. The converter uses the standard formula: the key channel is taken from the brightest RGB channel, and the three colored inks are what remains once that shared black is removed. Pure black and pure white are handled explicitly, so #000000 returns a clean 100% key instead of an error.

Enter a color any way you like: an rgb() string with commas or spaces, three bare numbers, a 3- or 6-digit hex code, or the red, green, and blue sliders. Everything stays in sync, so pasting a value moves the sliders and dragging a slider rewrites the value. The output shows each ink on its own card with a proportional bar, plus copyable CMYK, RGB, and HEX strings, and you can switch between 0, 1, or 2 decimal places.

One honest caveat: this is a formula conversion, not a press proof. Real printed color depends on the color profile, ink, and paper stock, so use these percentages as a reliable starting point and confirm critical brand colors with your printer. Starting from a hex code instead? Use the hex to CMYK converter. For screen-space conversions, try RGB to HSV or find the nearest named color with the color name finder.

Frequently asked questions

How does the RGB to CMYK conversion work?
Each RGB channel is scaled to 0 to 1, the key (black) value is 1 minus the brightest channel, and cyan, magenta, and yellow are the remainder of each channel after that black is removed. The results are shown as percentages from 0 to 100.
Will these CMYK values match my printed output exactly?
Not exactly. This is the standard device-independent formula, but printed color also depends on the printer profile, ink set, and paper. Treat the values as a solid starting point and confirm critical colors with a printed proof.
What input formats are supported?
rgb() and rgba() strings with commas, spaces, or slashes, bare number triplets like 226 61 40, percentage channels, and 3-, 4-, 6-, or 8-digit hex codes with or without the # prefix. Alpha is ignored because CMYK is an opaque ink model.
What happens with pure black or pure white?
Pure black (0, 0, 0) converts to 0% cyan, magenta, and yellow with 100% key. Pure white (255, 255, 255) converts to 0% on all four inks. Both cases are handled explicitly so the math never divides by zero.
Is my color data uploaded anywhere?
No. Everything runs in your browser; nothing is sent to a server.

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