Font size

Make sure the text is readable by carefully selecting font, colour and font size. To improve readability, users might want to increase font size. Make sure the text can be enlarged using the browser zoom or the features of the mobile device without losing information.

Contrast

Make sure the text is readable by ensuring enough contrast between text and background:

• Small text and images of text should have a contrast ratio of at least. 4,5:1 against its background.
• Large text (at 14 pt. bold or 18 pt. regular and up) should have a contrast ratio of at least 3:1 against its background.
• Incidental text or images pure for decoration or logotypes that are part of a logo or brand name have no such contrast requirements.

To check the requirements, you can use colour contrast analyser tools such as:

• Colour contrast analyser
• Tanaguru contrast finder
• Extensie Google Chrome

For info about why contrast matters: http://contrastrebellion.com/

Use of colour

Don’t use only colour to convey information. When colour is used to convey information (for example on a map of in a diagram), include another way to convey the information : textual labels, patterns, icons etc.

To understand more about colour blindness: http://wearecolorblind.com/

Visibility of links

Make sure that links can be distinguished from regular text, for example by using underlining for links. It is not enough to use a different colour for links.