Colour and contrast

Users who have a colour deficit are unable to distinguish between specific colours. As we age, our eyes are also not so easily able to differentiate between colours and we need higher levels of visual contrast.


Use of colour in documentsEnsure that you do not use colour alone to convey meaning. For example, you might use a specific colour with a specific shape to convey meaning.See the Vischeck and SimDis links below to see the effects of visual impairments.
Colour blindnessUse colours that can be distinguished by those with colour blindness.


Text and background coloursEnsure that there is sufficient contrast between text and background colour.To check if the colour contrast is sufficient for those with colour deficiencies or for those working with low resolution monitors, print your pages in ‘grayscale’. See the web links below for more information and good examples for effective colour contrast in digital content.
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