# Response Validators
In vREST, assertions can further invoke validators to validate the test case responses. A response validator is simply a JavaScript function. A test case passes if the assigned response validator returns true otherwise it fails.
# Types of Validators
vREST provides the following default response validators and also provides you a way to define your own custom validator.
Default Validator validates the expected and actual responses (response body) for an exact match. If the value doesn't match, it simply fails the test case. We need to define Expected Body for the test case if we choose this. Any variables in the expected body are first replaced and then provided to the validator for response validation.
Default Schema Validator validates the schema of the actual response instead of checking for an exact content match. We need to define Expected Schema for the test case if we choose this. If we use this validator, then we don't need to define the Expected Body.
Custom Validator validates the actual response in your own way. Most of the cases of response validation can be handled with the above default validators and built-in assertion operators. However, you may define your own custom validators/operator for customized response validation.
For more information on this, please read our guide on Custom Validator / Operator.