A catalog of Myndex Research content, including APCA articles & documentation, related code repositories, and resources.


Accurate Contrast
Using the APCA

INFO APCA Resources APCA Readability Criterion APCA/Main Repo
STATS version downloads  starsplain vanilla JS
APPS APCA Live Demo BPCA Live Demo CVD Simulator
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The Accessible Perceptual Contrast Algorithm

General Overview

APCA Technical Documentation

Social Media and Forums

Sciencey Stuff!

Maths! Theory! Vision Science! Photons on Parade!

For Developers


APCA Reviewed

A separate page comprised of the following listing of reviews is also available at APCA Reviewed, which is updated more frequently.

Independent Peer Reviews of APCA and
Third Party Comparisons vs WCAG 2

There are several independent researchers evaluating APCA, and additional third party comparitive reviews that include demonstrations of the functional superiority to existing methods. The first few listed below are technical reviews by peers evaluating the APCA math and methods, including journal published peer reviewed papers. Some in comparison to WCAG 2 contrast methods and guidelines.

APCA has been developed in the open for open peer review and discussion, and the reviews listed below were performed independently, the majority were completed without consulting the APCA developers. Reviews listed first are peer or academically oriented, and deal with theory, while reviews listed later are targeted more toward practicioners, designers, and developers.

Known Issues With WCAG 2 Contrast

The problems of 4.5:1 as a target for a guideline is that it not only impact those with impairments, but impacts standard vision as well. WCAG 2 contrast SCs affect 100% of sighted users. The inherent problems with the WCAG 2 contrast math have been known for some time and widely critisized. Including studies by others showing that color insensitive types are not well served.

The WCAG 2 contrast specs often cause enough problems for designers that it is ignored and today, some 86% of websites are failing WCAG_2 contrast per an automated survey—though some of these failures are not due to poor actual accessibility, but due to the perceptual inaccuracies of WCAG_2 contrast.

The unfortunate end result is a grave distrust of the WCAG 2.x accessibility standards overall, despite the many other important aspects of those standards.

Myndex Color Resources

Myndex Web Apps

On Readability & Contrast

GitHub Gists

Mini articles on technical topics, with examples

New Gists!

Contrast & Color Gists

A Listing of Significant (Legacy) Threads

These were some of the larger, in-depth issue threads & posts created on GitHub including the infamous thread #695. These posts contain useful information and research. Some of the information here may be superseded as some of these threads date back to the beginnings of the contrast research project.

APCA—The Revolution Will Be Readable

Tech Articles NOT About Color

Society & Technology

Other Tech Gists

Myndex on Other Sites

Myndex is top 3% on Stack Overflow!
profile for Myndex on Stack Exchange, a network of free, community-driven Q&A sites

The Lighter Side of Math & Photons…

The Art and Science of Applied Probability

In this career, I was using Applied Probability Methodologies for the Risk Assessment of short term ROI predictions related to high-variance cash-flow opportunities in finite-sized non-cooperative bidding groups where information is obliquely concealed as a function of multivariate strategies facilitating the predominately range-based tactics driven by randomized but nevertheless deterministic outcomes.

(…Sooo… this is more commonly known as Texas Hold ’Em Poker…)

For the record, Myndex is pronounced:

mind - ex
\ ˈmīn-ˌdɛks \

When George Eastman invented the word “Kodak” one of his criteria was that “it won’t be mispronounced”. I guess I missed that day. Ooops.

Just how many patent attornys does it take to rotationally engage a helical conducting thread of an illumination apparatus further comprised of a sealed, evacuated glass envelope containing two or more conducting filament holders which electrically connect and physically support a coiled electrically conducting but resistive filament, preferentially fabricated from a tungsten alloy, to the aforementioned helical threads, which further engage into a helical conducting receptacle, such that when an electrical power source of sufficient voltage and current is applied to the receptacle input conducting connectors, the voltage and current is henceforth transferred to the helical conducting threads of the illumination apparatus and thereto across the conducting filament holders and through said filament such that it shall be caused to incandesce and emit visible irradiance according to the laws of blackbody radiators?

The Answer as to how many: a plurality

Welcome to the very bottom of the page!

Here at the very bottom of the page, we dare to ask the question, “do two lights make a dark?”

Click for Answer YES, two lights make a dark, if together they draw so much current they **blow a fuse** 💥.