2008
Colour Contrast Check - snook.ca
by greut & 30 others (via)
The Colour Contrast Check Tool allows to specify a foreground and a background colour and determine if they provide enough of a contrast "when viewed by someone having color deficits or when viewed on a black and white screen"
better color checker
G18: Ensuring that a contrast ratio of at least 5:1 exists between text (and images of text) and background behind the text | Techniques for WCAG 2.0
by greut
The objective of this technique is to make sure that users can read text that is presented over a background. For Success Criterion 1.4.3, this technique describes the minimum contrast ratio for text that is less than 18 point (if not bold) and less than 14 point (if bold). For Success Criterion 1.4.5, this technique relaxes the 7:1 contrast ratio requirement for text that is at least 18 point (if not bold) or at least 14 point (if bold).
with the formula and advices
2005
1
(3 marks)
