The Short Answer
The ADA (Americans with Disabilities Act) is a civil rights law that prohibits discrimination against individuals with disabilities. WCAG (Web Content Accessibility Guidelines) are technical standards created by the W3C that define how to make web content accessible.
In short: The ADA is the *law*, and WCAG is the *technical roadmap* to comply with that law.
The ADA Explained
Passed in 1990, the ADA requires "places of public accommodation" to be accessible. While it predates the modern web, the Department of Justice (DOJ) has consistently maintained that websites and digital apps of covered entities must also be accessible.
However, the ADA does not explicitly dictate *which* technical standard websites must follow. It simply mandates effective communication and equal access.
WCAG Explained
WCAG provides testable, objective criteria for digital accessibility. It is the most widely referenced accessibility standard in the world.
- Levels: It is divided into three conformance levels: A (minimum), AA (standard), and AAA (enhanced).
- Versions: The guidelines evolve (2.0, 2.1, and the current 2.2).
The Legal Consensus
Because the ADA lacks a specific technical standard, US courts and the DOJ look to WCAG. In almost all legal settlements and DOJ consent decrees regarding website accessibility, the mandated standard for compliance is WCAG 2.1 Level AA (with momentum shifting towards WCAG 2.2 AA).
If your website conforms to WCAG 2.1/2.2 AA, you are widely considered to be in compliance with the digital requirements of the ADA.
Why Aim for WCAG
Without WCAG, "accessibility" is subjective. Adopting WCAG 2.2 AA as your internal standard gives your design and engineering teams clear, measurable goals and lowers your legal risk under the ADA.