# Color contrast ratio

> Color contrast ratios represent the difference in brightness of the colors in your app when represented on a computer display. Selecting an adequate contrast ratio makes your app interface more readable, especially to users with moderately low vision acuity.

Color contrast ratios represent the difference in brightness of the colors in your app when represented on a computer display. Selecting an adequate contrast ratio makes your app interface more readable, especially to users with moderately low vision acuity.

* The color contrast ratio between text color and background color in your app must be at least 4.5:1.
* Large-scale text, or images containing large-scale text must have a contrast ratio of at least 3:1.
* For more details on accessibility standards concerning color contrast, refer to [WCAG 2.2](https://www.w3.org/WAI/WCAG22/Understanding/contrast-minimum.html).