Avoid using CAPTCHAs in forms

The Challenge
A CAPTCHA is a kind of test inserted into Web-based forms that only humans can answer correctly. The test's purpose is to prevent computers from automatically completing and submitting forms, thus generating spam and other problems. The form can be submitted successfully only if the CAPTCHA is deciphered and the test answered correctly. Many CAPTCHAs are visual or pattern-recognition tests that screen readers can't interpret, as in the example below.

Example of visual CAPTCHA

Other types of CAPTCHA are inaccessible to people with audio, learning, or other disabilities.

Solutions

  • Instead of using a visual or audio CAPTCHA, use question-and-answer tests. Examples:
    • Arithmetic: If three ducks join two ducks on the pond, how many ducks are there?
    • Text: What is the opposite of "black?"
    • Keep in mind that such questions must be very simple and still can exclude people with cognitive disabilities. Try to match the test to the expected audience.
  • Use a box that the user has to check or uncheck.