This tool will help you test and validate your DMARC record. Once the domain has been entered, view and evaluate all possible options that are implemented.
DMARC (Domain-based Message Authentication Reporting and Conformance) is a free and open email authentication protocol that allows a sender to notify receivers that their emails are protected either using SPF or DKIM. It also advises the receivers on what to do if an email fails to pass either of these authentication methods. The main purpose of DMARC is to protect domain owners from email spoofing.