RGB to CMYK Converter: Screen to Print Values
Convert RGB screen colors to CMYK print values instantly.
Last updated
Contrast on white & black
WCAG 2.1 contrast ratio of #2563EB against a white and a black surface.
AA needs 4.5:1 for normal text and 3:1 for large text (18pt, or 14pt bold); AAA needs 7:1. Use this to choose white or black text over the color.
About this conversion
RGB (Red, Green, Blue) is the color model used by every screen and digital display. Colors are created by mixing light, with each channel ranging from 0 to 255. CMYK (Cyan, Magenta, Yellow, Key/Black) is the subtractive model used in commercial offset printing and professional inkjet printers, where colors are produced by absorbing light through layers of ink on paper.
When you design on screen in RGB but need to send files to a printer, you must convert your colors to CMYK. The two color spaces do not overlap perfectly. RGB can represent vivid neon colors that CMYK inks cannot reproduce, and vice versa. This tool uses the standard mathematical conversion, which gives you a reliable starting point for print-ready values.
For critical print work such as brand identity, packaging, or fine art reproduction, consider verifying the CMYK output against a physical proof. ICC color profiles and professional proofing workflows can further refine the match between what you see on screen and what comes off the press. Print our CMYK test page to verify that your printer reproduces each ink channel accurately before committing to a production run.
For a deeper read on which colors survive the conversion and which ones don't, see our RGB vs CMYK guide.
Worked examples
Real conversions this tool produces — enter the inputs to reproduce each result.
Sending a screen blue to a four-colour press
Input
- Red (R)
- 37
- Green (G)
- 99
- Blue (B)
- 235
Result
- Cyan (C)
- 84%
- Magenta (M)
- 58%
- Yellow (Y)
- 0%
- Black (K)
- 8%
rgb(37, 99, 235) returns 84/58/0/8 — but feeding 85/60/0/8 the other way gives rgb(35, 94, 235), not the original. The round trip doesn't close because integer rounding loses a little each way; never assume RGB→CMYK→RGB is lossless.
A pure web orange built for print
Input
- Red (R)
- 255
- Green (G)
- 102
- Blue (B)
- 0
Result
- Cyan (C)
- 0%
- Magenta (M)
- 60%
- Yellow (Y)
- 100%
- Black (K)
- 0%
A maxed red-and-no-blue orange needs zero cyan and zero black — just magenta and yellow. The catch: this bright an orange sits outside CMYK gamut, so the print will read more muted than the screen.
Pure black, the K-channel shortcut
Input
- Red (R)
- 0
- Green (G)
- 0
- Blue (B)
- 0
Result
- Cyan (C)
- 0%
- Magenta (M)
- 0%
- Yellow (Y)
- 0%
- Black (K)
- 100%
This converter sends black to 100% K only — clean for text. For large solid black areas, press operators usually add a "rich black" undercolour, which this naive formula won't generate.
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Color conversions are mathematical approximations. For critical color work, verify against physical swatch books and printed proofs. See our methodology and full disclaimer.
Frequently Asked Questions
Why do screen colors look different when printed?
Screens use RGB (additive light) while printers use CMYK (subtractive ink). The two color spaces don't overlap perfectly. Some vivid screen colors can't be reproduced in ink, and some deep print colors can't be shown on screen.
What does the K in CMYK stand for?
K stands for Key, referring to the black ink plate. Black is added separately because mixing cyan, magenta, and yellow inks alone produces a muddy brown rather than true black, and using a dedicated black ink is more economical.
Should I convert to CMYK before sending files to a printer?
For professional print work, yes. Converting to CMYK before sending gives you control over how colors translate. If you send RGB files, the printer's RIP software will do the conversion automatically, which may not match your expectations.
Cite or embed this tool
Cite this tool
PrinterTools. (2026). RGB to CMYK Converter: Screen to Print Values [online tool]. https://printertools.net/tools/rgb-to-cmykEmbed this tool
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<a href="https://printertools.net/tools/rgb-to-cmyk" target="_blank" rel="noopener" style="display:inline-flex;align-items:center;gap:8px;padding:10px 14px;border:1px solid #e2e8f0;border-radius:8px;background:#ffffff;font-family:system-ui,-apple-system,sans-serif;font-size:14px;line-height:1.3;color:#2563eb;text-decoration:none;">RGB to CMYK Converter: Screen to Print Values — free tool by PrinterTools</a>More Print calculators
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