Automated accessibility testing can be done using Pa11y, an open source tool that tests web pages and provides reports on issues like proper heading structure, alternative text for images, and color contrast. Pa11y is run from the command line or through a dashboard and generates reports in formats like JSON, HTML, or PDF to help developers identify and fix problems to meet accessibility standards and regulations. The document provides an example of using Pa11y to test a Drupal site and generate different report types.