What are good contrast colors for a GUI application

1. What color is best for contrast?
2. What is color contrast in UI design?
3. How many colors should a UI have?

What color is best for contrast?

For example, colors that are directly opposite one another on the color wheel have the highest contrast possible, while colors next to one another have a low contrast. For example, red-orange and orange are colors that have low contrast; red and green are colors that have high contrast.

What is color contrast in UI design?

Summary: When visual design elements appear clearly different (for example, have contrasting colors) users easily deduce that the contrasting item is different or special in some way. So if it actually is different, this enhances usability.

How many colors should a UI have?

A color palette shouldn't exceed six colors, but to start with, most designers opt for three or four. These should comprise one dominant color, one standard color (used primarily for text, such as black or grey), and two accent colors.