This is a Test design technique where the experience of a tester is used to find the components of software where defects might be present.

It is mostly done by experienced testers who can use their past experience to find defects in software.

Error guessing has no rules for testing, it only uses the testers previous skills.

In error guessing testers can think of situations where software will fail. For example:

  1. Division by zero
  2. Pressing submit button on form without filling any entries.
  3. Entering wring data in the fields and checking software behavior.