DMARC record generator
Build the TXT record that tells receivers what to do with mail that fails authentication while claiming to be from your domain. Nothing you type leaves your browser.
Your record
Create a TXT record at _dmarc.example.com with this value:
v=DMARC1; p=none
Before you tighten it
This publishes a policy that changes nothing yet, which is the right place to start. Leave it running for a few weeks with a reports address so you can see every service sending as your domain, including the ones nobody remembers setting up.