Re: [External] CFC - color contrast formula errata

+1 with the minor editorial change to make contrast-minimum and contrast-enhanced Understanding documents align. The enhanced version includes this line: Flare from [[IEC-4WD]] paper by M. Stokes et al.

The reference that was removed is the one that Stokes authored, and this is correctly reflected in the minimum version.


Andrew Kirkpatrick
Director, Accessibility

From: Alastair Campbell <>
Date: Thursday, May 13, 2021 at 5:31 AM
To: WCAG <>
Subject: [External] CFC - color contrast formula errata
Resent-From: WCAG <>
Resent-Date: Thursday, May 13, 2021 at 5:30 AM

Call For Consensus — ends Monday May 17th at noon Boston time.

The Working Group has discussed a change to the color contrast formula to update the dated reference to an old spec. It includes a note saying that it won’t affect the values generated from the formula. This change would add an errata to WCAG 2.0 & 2.1, and be included in 2.2.

The specific changes are detailed in this pull request:

Call minutes:

If you have concerns about this proposed consensus position that have not been discussed already and feel that those concerns result in you “not being able to live with” this decision, please let the group know before the CfC deadline.

Kind regards,



@alastc /<>

Received on Thursday, 13 May 2021 14:32:56 UTC