Microsoft Office products have built-in accessibility checkers, which are often located under the Review tab. If you cannot locate the accessibility checker simply type accessibility into the search or help function.
Grackle Docs is a Google add-on that checks your Google document for accessibility.
Adobe Acrobat Pro DC has a built-in accessibility checker. The accessibility checker can be found under the Tools panel on the right hand side.
Goal: To make the navigation and clarity of content perceivable by all users and the five senses.
Goal: To make content navigation operable by all users.
Goal: To make content and technology understandable to all users.
Goal: To make content robust enough that screen reader technology can interpret it correctly.
The W3C Web Content Accessibility Guidelines 2.0 define specific color contrast ratios that must be met in order comply at particular levels. In order to meet the guidelines at Level AA, text or images of text must have a contrast ratio of at least 4.5:1 (or 3:1 for large text).
When designing the color scheme of a website, web page, or document, be sure to consider whether there is sufficient contrast between foreground text and background. Some users may have difficulty perceiving text if there is too little contrast between foreground and background.
Use the WebAIM Color Contrast Checker to select different colors and determine contrast ratios.