Every color on your phone screen is built from three lights: red, green, and blue. This is the RGB color model, an additive system. Combine all three at full intensity and you get white. Turn them all off and you get black. Vary the intensities and you can produce millions of colors. Each channel typically has 256 levels, from 0 to 255, giving 16.7 million possible combinations.

RGB is the native language of digital displays. Monitors, phones, cameras, and scanners all work in RGB. Designers creating work for screens build color values in this space. CSS uses rgb() and hex codes like #FF5733. The model has a wider gamut than CMYK, meaning it can display more saturated colors than printing can reproduce. That gap causes frustration when a vibrant screen design prints dull.

Key points

• Additive: light is added together.
• Used by all digital displays.
• Values range from 0 to 255 per channel.
• Hex codes are shorthand for RGB values.

When designing for both screen and print, keep in mind that RGB and CMYK will never match exactly. Choose colors that survive the conversion.