Three psychophysical experiments were conducted to investigate the colour appearance changes between different sizes under various media or viewing conditions. The results are highly consistent that when increase stimulus size, the colour will appear to be lighter and more colourful with little change in hue. (C) 2010 Wiley Periodicals, Inc. Col Res Appl, 36, 201 - 209, 2011; Published online 17 June 2010 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/col.20610