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Re: 1.4.3 Contrast (Minimum) - Large-scale text

for

From: Jared Smith
Date: May 14, 2012 5:04PM

On Mon, May 14, 2012 at 4:02 PM, David Ashleydale wrote:

> For one thing, I find this odd because the recommendation for 1.4.4 Resize
> Text is to not use "fixed" font sizes like points. Is 1.4.4 still valid in
> today's web environment?

Because nearly all modern browsers these days resize pixel-based fonts
and also support page zoom, I do believe the restriction against
absolute font sizes is dated and irrelevant. See other concerns about
this requirement at http://webaim.org/blog/wcag-next/#textsizing

> For another, what's the best way to determine what "18 point" is in other
> measurement systems?

As you note, it's a bit tricky. I'm not sure I entirely understand
what WCAG is actually requiring here, but one way you can do this is
to measure the pixel text height of a particular font face at default
size (e.g., 100% or 1em). Firebug provides a good way to get the pixel
size. Multiply this number by 1.2 to get the minimum "Large text" size
for bold text and multiply by 1.5 to get the minimum "Large text" size
for non-bold text. Regardless of how the text is sized in the
document, the pixel heights can be measured and compared to these
baselines.

As with all things in conformance, common sense is important. Even if
something does not meet the WCAG thresholds, if it looks like it needs
more contrast, IT DOES!

Jared