Contrast goes in tandem with color. Apart from making buttons prominent for users with good vision, setting the right contrast makes them accessible to visually impaired users. Approximately 4.5% of the global population live with color blindness (that's 1 in 12 men and 1 in 200 women).^[1] At least 2.2 billion people have a near or distance vision impairment, and about 39 million people are believed to be completely blind.^[2] As designers, we should remember to be empathetic and keep inclusivity as a top priority.

According to the WCAG recommendations, the color contrast ratio between background and foreground for normal text should be 4.5:1.^[3] To calculate the contrast ratio between the button's label and background color and ensure it meets WCAG, you can use Coolors or WebAIM checkers.