Typeface Accessibility
Checking Flash version...
Defnitions...
Legible - character subtends an angle to the eye greater than 5.5 minutes of arc.
Readable - character subtends an angle to the eye greater than 11 minutes of arc.
Easy-to-read - character subtends an angle to the eye greater than 16 minutes of arc.
Notes
Error checking... This tool performs no error checking. If you put in a dumb hex value, it will probably break!
Contrast checking... The contrast modelling is a massive guess. I've found some studies that suggest a sort of 1/(1-x) relationship between contrast ratio and required letter height, but nothing concrete. The start and end points are known: W3C state that once the contrast ratio is smaller than 1:7 there is no further improvement in legiblity to be had, and it makes sense that the required letter height should tend to infinity as contrast tends towards 1:1. The modelling in the middle, however, is pure guesswork. If that sort of thing floats your boat, you can view the function used.