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Re: trying a second time looking for color contrast rules

for

From: Lucy Greco
Date: Aug 26, 2014 11:39AM

perfect this was just what i needed. i always get so bogged down in reading
through the specs and never find the information i am looking for this was
vary clear thanks Lucy


On Mon, Aug 25, 2014 at 8:24 PM, Bim Egan < <EMAIL REMOVED> > wrote:

> Hi Lucy,
>
> WCAG 2.0 Success Criterion 1.4.3 Contrast (Minimum) requires a contrast
> ratio of at least 4.5:1, for "normal" sized text or images of text.
> For "large" text, (or images of large text), the minimum contrast ratio
> is 3:1.
> Large or larger scale text is defined as 18pt at normal font weight or
> 14pt for bold font weight.
> There are exceptions, where no contrast minimum is required, these
> include: inactive user interface controls, images of text where the text is
> pure decoration and text in logos.
> 1.4.3 is a Level double-A requirement. The full description of this
> success criterion is easiest to find immediately below the H1 in the
> Understanding document at:
> http://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-
> audio-contrast-contrast.html
>
> The triple-A Success Criterion is 1.4.6 (Contrast Enhanced). This
> requires a minimum contrast ratio of 7:1 for "normal" sized text or images
> of text and a contrast ratio of 4.5:1 for "large" or larger scale text or
> images of text. The size definitions and the exceptions are the same as
> in 1.4.3.
> The Understanding document for 1.4.6 is at:
> http://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast7.html
>
> For guidance on relative sizing equivalents the above documents say that
> 18pt is roughly 1.5em or 150% of the body text when the body text is 1em or
> 100%. 14pt bold is roughly equivalent to 1.2em bold or 120% bold where body
> text is 1em or 100%.
>
> HTH.
>
> Bim
>
>
>
>
>
> On 25/08/2014 23:29, Lucy Greco wrote:
>
>> hello:
>> sorry about my last message.I have recently switch my mail and have not
>> worked out all the kinks yet.
>> I am writing a short artacle about color contrast and was hoping some one
>> could send me a plain text vertion of what the rules and percentages are
>> for color contrast in W3C2.0 i normaly get a sited person to check these
>> and don't really know what the percentages should be in all situations
>> thanks lucy Lucia Greco
>> Web Accessibility Evangelist
>> IST - Architecture, Platforms, and Integration
>> University of California, Berkeley
>> (510) 289-6008 skype: lucia1-greco
>> http://webaccess.berkeley.edu
>> Follow me on twitter @accessaces
>> >> >> >>
>>
> > > >



--
Lucia Greco
Web Accessibility Evangelist
IST - Architecture, Platforms, and Integration
University of California, Berkeley
(510) 289-6008 skype: lucia1-greco
http://webaccess.berkeley.edu
Follow me on twitter @accessaces