Historically, primary colors have been taught as red, green, and blue. While there has been debate over how the human eye actually perceives color, sometimes leaning closer to CMYK, this distinction doesn’t matter much for UI designers.

What does matter is how color works on screens.

On the web and in digital interfaces, we use the RGB color model, which stands for Red, Green, and Blue.

RGB is an additive color model, meaning colors are created by adding light to black. Every color you see on a screen is a combination of red, green, and blue values.

For example:

Each RGB value adjusts the intensity of its color channel, shaping the final appearance.

Hex colors are simply another way of representing RGB values. Instead of three numbers, hex values use a six-character code starting with a #.

For example:

Each pair of characters represents red, green, and blue respectively. Designers often shorten repeating values like #EFEFEF to make them easier to read and remember.

Most design tools, including Figma, primarily use hex values, though you can easily convert between RGB and hex using online tools.

Colors can be categorized by temperature: warm or cool.

Warm colors contain higher amounts of red and yellow. They evoke:

This is why red is commonly used for error messages, it demands attention and feels aggressive by design.

Cool colors contain higher values of blue. They are often associated with:

This explains why many tech and social platforms, like LinkedIn, Facebook, and older versions of Twitter, rely heavily on blue in their branding.

Tints and shades are essential for creating usable UI color systems.

These variations allow designers to create monochromatic color palettes, which are extremely useful in UI design.

For example, a primary brand color might be used for a main button, while lighter tints of that same color can be used for hover states, backgrounds, or secondary elements, avoiding visual overload.

Understanding these three properties helps you fine-tune color choices.

In UI design, lightness is especially important for contrast, accessibility, and readability.

The color wheel is a fundamental tool for creating color harmony. It contains 12 standard color families arranged in a circular format.

Each section of the wheel represents a family of colors that can be modified through tints, shades, saturation, and lightness. While there are millions of possible color combinations, UI design works best when you choose:

Designers typically rely on five traditional color schemes:

In practice, monochromatic and complementary schemes are the most commonly used in UI design due to their clarity and balance.

Choosing colors manually can feel overwhelming, which is why tools are invaluable.

Some popular tools include:

These tools allow designers to experiment freely while maintaining harmony and consistency.

If you’re stuck, exploring existing palettes can be a great starting point. Many tools let you browse palettes by:

Once you find something that fits your project, you can copy the hex values directly into your design system.

Color mastery in UI design doesn’t happen overnight. It’s a balance of theory, experimentation, and practical application. By understanding how RGB and hex values work, recognizing emotional impact, and using the right tools, you’ll create interfaces that are not only beautiful, but effective.

I don’t know why I have to say this, but what works for me might not work for you, and vice versa. Most of the time, you just need to think things through and figure out what works best for you. I’m not trying to be rude, but you could solve a lot of your problems if you simply used your brain. This applies to every aspect of your life, not just design.