When designing a brand new logo for a client, we made ourselves de question of how much contrast is enough contras between elements. Mainly when used in a digital format and translated into other colour uses.
At first glance, the WCAG 2.0 AA guideline for contrast minimums appears to be one of the easiest, most straightforward success criterion to achieve. Yet, it is a real possibility for a site meeting WCAG 2.0 AA guidelines to be difficult to use, or even be unusable, for low vision users. The reason for this is that WCAG 2.0 contrast requirements are limited to text.
This is what Understanding WCAG 2.0 tells us about contrast minimums:
- Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;
- Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
- Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.