RGB to CMYK is described as 'Your print provider does not accept RGB images? You have to deliver images in the CMYK colorspace but you don't have access to a professional tool to convert an image from RGB to CMYK?' and is an website in the system & hardware category. There are 2 alternatives to RGB to CMYK, not only websites but also apps for Mac, Windows and Linux. The best RGB to CMYK alternative is Cyan, which is both free and Open Source.
Cyan is an open source cross-platform image viewer and converter, designed for prepress (print) work. Like converting an image from RGB to CMYK, or the other way around. Cyan supports color profiles complying with the International Color Consortium (ICC) standard, and strives to...
Convert images from CMYK to RGB color space (using professional color profiles) with this free online converter.
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