Bright on screen, dull on paper: CMYK vs RGB

You designed the wedding invitation or the logo on screen and the colours glowed exactly as you wanted. The printed copies tell another story: the turquoise has gone greyish, the purple looks muddy, the bright green has lost its punch. On top of that, the print shop asked you to "send the file in CMYK" before they would start, and nobody explained what that means. This guide answers both questions together: why the colour faded, and what you should hand over.

The short answer: nothing is wrong with your file. A screen and a sheet of paper do not share the same range of colours, and some colours a screen can show simply cannot be printed with ink, whatever the settings. In other words, the problem is usually not your design but the narrower space every colour has to squeeze into on its way to paper.

A screen gives off light, paper only reflects it

Every dot on your phone or monitor produces its own light; the colour you see is the colour of a tiny lamp shining towards you. Paper makes no light at all. It sends back part of the light already in the room, and ink works by swallowing some colours out of that reflection. Something that glows will always look brighter than something that reflects, which is why a colour at full blaze on screen may never reach the same liveliness on paper.

The two worlds have names. RGB counts the three lights of a screen; CMYK counts the four inks of a printing press: cyan, magenta, yellow and black. When a printer says "send it in CMYK", they mean "give us the file in the language our machine speaks". If you do not convert it yourself, the print shop does it for you. The result hits the same limit either way; you just discover the surprise after the job is printed.

Which colours fade and which stay the same?

Picture every colour a screen can produce as one area, and every colour ink can print as a smaller area inside it. The smaller one fits mostly within the larger, but the bright edges of the larger one stay outside. The full set of colours a device can reproduce is called its gamut; colours that exist on screen but not on paper are called "out of gamut" in the print trade.

The ones left outside are nearly always saturated, luminous colours: neon green, electric blue, vivid turquoise, bright violet and fluorescent orange. Browns, beiges, skin tones, navy, burgundy and greys sit in the shared area, so if your design is built from those you can expect few surprises. An out-of-gamut colour does not vanish when printed; it is pulled to the nearest printable shade at the border. That shift is exactly what your eye reads as "faded".

Why didn't the converter warn you? Formula versus colour profile

The CMYK to RGB converter on this site uses a formula and applies no colour profile (ICC); the tool's own page says so plainly. A formula assumes perfect inks, and the consequence is surprising: by the formula, 100 per cent cyan ink equals #00FFFF, the brightest turquoise a screen can show. Real cyan ink on paper comes nowhere near that brilliance.

For the same reason a formula never calls a colour "unprintable". Give it the turquoise #00C8FF and it returns cmyk(100%, 22%, 0%, 0%); convert those percentages back and you get #00C7FF, as if almost nothing were lost on the way to paper. The table shows a few examples: on the left the colour on screen, in the middle the formula's answer, on the right the usual tendency in a real print run.

A colour profile, by contrast, is a file that records what one particular press, ink and paper actually produce together. Photoshop, Illustrator and InDesign convert according to those measurements and can flag colours that will not print. So do not treat the tool's percentages as the final values for the press; use them as a starting point when you tell the printer "I want something close to this colour".

Preview the printed result on your own screen

If you designed in Photoshop, the View menu has a Gamut Warning command that paints unprintable pixels grey; Shift + Ctrl + Y switches it on in Windows, Shift + Command + Y on a Mac. Which printing condition the warning is based on is set under View > Proof Setup, so pick the profile your printer names. Wherever you see grey patches, the print will shift.

In Canva, choose Share, then Download, and pick PDF Print as the file type; the Color profile list then offers CMYK. That option does not appear on Canva's free plan, in which case you send the file in RGB, leave the conversion to the print shop and only see the outcome on the proof.

Do not panic when colours dim the moment the file is converted. The program is now showing you what paper can really carry, and that duller picture is a closer forecast of the print than the bright one. Screen brightness also fools the eye, so avoid judging colours with your display turned all the way up.

Questions to ask before you send the file

Print shop staff hear these questions every day. Asking them does not make you look inexperienced; it is the cheapest way to prevent a wrong print run. Write the answers down and you can reuse the same settings with the same printer next time.

• Which colour profile do you work with, and which one should I convert to?
• Which paper will it be printed on, coated or uncoated? Uncoated stock absorbs ink, so the same values look flatter.
• If I send RGB, will you do the conversion, or must it be CMYK?
• Can I see a proof before the run, on screen or on paper?
• If my main brand colour cannot be matched in CMYK, can we use a spot ink such as Pantone, and what does it cost?
• Should black text be printed in black ink only?

Record the screen colour and the print colour separately

One value is not enough for a logo or a brand colour. Websites, slides and social media use HEX or RGB; the press uses CMYK. Settle both once, write them down, and you will never have to convert from scratch for every job. The safest version of the CMYK value is the one confirmed on a printer's proof.

If you only have one side, fill in the other with the CMYK to RGB converter; it also reads HEX codes directly. If your designer gave the colour as hsl(…), that tool will not recognise it, so first turn it into HEX with the Colour Code Converter and then move on to CMYK. Keep in mind that the CMYK percentages you get there are a first estimate; the printer's profile and proof have the final say.

Frequently asked questions

What happens if I send an RGB file to the printer?

Most print shops convert it to CMYK with their own profile and print it; some send it back and ask for CMYK. Either way, bright colours hit the same limit. If you want to see the difference before the run, ask for a proof.

Why did the colours dim as soon as I converted to CMYK?

The program now only shows colours that can be printed. Those at the bright edge of the screen's range were pulled to the nearest printable shade. That is not damage; it is a more honest preview of the printed result.

Can the tool on this site convert my image or PDF to CMYK?

No. The CMYK to RGB converter translates individual colour values; it does not change the colours inside an image or a PDF file. For the file itself, use the print settings of your design program or let the print shop handle it.

What is Pantone, and do I need it?

Pantone is a colour system printed with a premixed special ink rather than a blend of the four process inks. It can reach some vivid colours CMYK cannot. Small jobs such as business cards or invitations rarely need it; if your brand colour is critical, ask the printer about the cost.

Does the same CMYK value give the same colour at every printer?

Not exactly. Paper type, press and profile all change the result. The same percentages look livelier on coated paper and flatter on uncoated paper. For colour-critical work, ask every new printer for a proof.

Last updated: October 12, 2026