If you are interested, or already work in graphic design, you for sure have read the terms “RGB” and “CMYK”. Chances are you may have also seen these letters in a few places, including projectors and in printer settings. But what are these terms precisely, and how do they affect your work in the digital industries? While introductions to graphic design while likely touch on theory and history, knowing the difference between these two color profiles is a hard skill that will be very useful for anyone in the creative industries. Keep reading to learn the difference between RGB and CMYK, the origin of these terms, and their practical uses in creative projects and beyond!
RGB – what is it?
To explain what RGB is (and yes, RGB as in “RGB Latte”!), we’ll need to start with a bit of theory. RGB stands for Red, Green, and Blue. When added together as light form, these three primary colors overlap creating three secondary colors, and, if all three are in equal intensity, meeting in the middle as white. This is the reason why this is referred to as an “additive color process”.
Here you can see the Red, Green, and Blue breakdown of an image. Image via Wikimedia Commons.
This principle has been key for electronic devices that display images, such as screens and projectors (did it ever happen to your that when looking towards a projector and blinking, you may have sensed a quick flash of red, green, or blue on your eye?). With the endless combination of these three different colors at different intensities, a device is therefore able to replicate a vast range of colors.
Projectors and televisions between the 1950’s and early 2000’s used CRT technology, with each of the three color channels projected separately. Image via Soundandvision.com
Now, as a designer you will need to know when to use RGB color mode in your visual projects. The answer is simple: use RGB whenever your project is meant to be visualized on a screen. This means any sort of visual media meant to be displayed on a projector or screen, as well as meant for digital screens such web or mobile devices, will need to be produced in an RGB color format.
When to use RGB Color Mode
Visual-creation software (for example, Adobe Photoshop or Adobe Illustrator) will allow you to check this setting at the start of a project. When setting up a new document aks yourself: “Will this be a digital project or a print project?”. If the answer is “digital”, then the right RGB is your setting. As a reminder, digital projects include any sort of web and apps, online campaigns such as display ads and social media, as well as digital photography and illustrations:
There are a few formats that will work wonderfully with files saved in RGB Color modes.
-Save your files in JPG or JPEG to produce a file that won’t be too heavy, that will preserve good quality, and that will be universally accessible by users.
-Save your files in PNG especially if you are working with web projects. You will be able to make transparent files in smaller sizes, which is particularly useful for icons, and it’s a standard format for other web elements like banners.
-If working with vectors, you can save your project in EPS or SVG format.
-Save your files in .PSD or .AI to if you use Adobe Photoshop and/or Illustrator. This is the best idea if you need to preserve editing capabilities for your files.
-Saving an RGB file in PDF is still a safe bet, plus it’s very universal.
CMYK – what is it?
Now on to CMYK. As you may have guessed, these letters also stand for colors: Cyan, Magenta, Yellow and Key (Black). If you have a certain model of printers, you may have seen these four colors represented as a specific cartridge. This is because this is the color format for print media. Color cartridges from printers include these three colors. Alternatively, printers may four have color cartridges and allow you to change them individually.
Cyan, magenta, yellow, and key (black) are the four standards colors in color printing.
In contrast to RGB, CMYK is a subtractive color process. This is because the sheet starts as a white surface, on which layers of ink of the four different values mentioned are added to create the preferred color by reducing the brightness of the original surface. When all ink colors are surfaced on each other, the result is pure black.
Here you can see the CMYK printing breakdown for this image. The “Detail View” allows you to see how via Dot-Matrix printing, a printer is able to give the illusion of color via the use of CMYK. Image via Baginco.com.
When to use CMYK Color Mode:
As a designer, you will need to know to use CMYK color mode for any print project. This includes any sort of printed marketing material, a print-version of your portfolio, product packaging, designs meant to be printed on fabric, and anything else your imagination can come up with.
Now, another pro tip from us. Unless you are seasoned with the printing process – ASK the printing service that you will use for your projects to tell you what file format they prefer, as well as any other technical specs they require based on the results you want to achieve. You will likely be safe with a JPG/JPEG PDF file (.PSD or .AI/.EPS as well if the print shop is a more specialized one). The standard for print shops will be TIFF. Once more, it’s better safe than sorry, so call your shop in advance and ask what specs they need for the results you want.
What happens if I use the wrong color mode for the type of project I needed?
If you create a screen project in CMYK, or a print color in RGB…. Likely nothing much will happen. Technically speaking, you will just not have the correct colors you chose for your project. Many printers will automatically “interpret” an RGB color profile in CMYK before printing it, but as we stated, this will result in some colors looking simply off.
Can I switch color modes?
Yes, but we do not recommend doing it without any further adjustments. The answer comes down again to color fidelity: if you create a document for web in RGB, then convert it to CMYK to also have it printed, some colors will look off.
What if I have a project for which I need both a Web and Print version?
We asked Glo Vallejo, a professional graphic designer and illustrator with years of hands-on experience in both web and print projects. Here is her advice:
I suggest working with an RGB color profile as it allows for richer editing properties. You can then save a separate version of your file that will be used for print, convert to CMYK profile, and then fix any color issues that may have appeared in the process. Glo’s pro tip? Add bleed to the CMYK version for printing.
Also, be aware that the colors used will not always look the same in both versions, simply because screens can display colors that cannot be reproduced in print.
And that’s it – we hope this article has shed some light in the “RGB vs. CMYK” mystery. There are many terms like this that are essential to the practical side of your creative process. We leave you some further reading, as this is truly a vast topic with lots of nuances and technical terms:
The Comprehensive Guide to Saving Images for the Web
How to Choose the Best Image File Format for Your Website
Exporting, Packaging or Saving Your File for Print
Types of Printers
Colours explained: CMYK vs Pantone
May we suggest you also discover this list of websites where you can generate color gradients. Use them for your projects, you will now know what color profiles to use!
We also leave you with some other Frequently Asked Questions in case you’re in a rush:
What is better RGB or CMYK?
An RGB color profile is meant for anything meant to be projected or displayed on a digital screen. A CMYK color profile is meant for anything meant to be printed.
What is the difference between RGB and CMYK
As a color profile, CMYK for print media because it matches the colors that are used by printers: Cyan, Magenta, Yellow, and Key (Black). A printer will layer these colours in a way that will create the colors that you are printing.
Do you use CMYK or RGB for print?”
For projects meant for print media, you use a CMYK color profile
Should I convert RGB to CMYK for printing?
Ideally, yes. If you don’t, your printer will likely “interpret” the RGB colors as CMYK, which could result in some looking a bit off. When you convert RGB to CMYK, you will still need to adjust colors a little bit in case they changed during the color profile switch