Email Authentication
SPF record check
SPF lists the servers allowed to send email as your domain. Without a valid one, your mail lands in spam and forgeries get through.
Check this on your own domain now. It is free with a DomainGuard account and works on any domain. The check reads only what your domain publishes, and gives you a report you can send to whoever runs your website.
What we look at
We read the TXT record at your domain that starts with v=spf1 and check that there is exactly one, that every term in it is valid, that it ends with an all (or a redirect), and that any host named in an a: or mx: term actually has an address. We cannot see who sends mail for you, so whether it lists every sender is the one part you have to confirm yourself.
Why it matters to your business
When a customer's mail server gets a message claiming to be from you, SPF is one of the first things it checks. No SPF, or a broken one, and your real invoices and quotes start going to junk folders, while someone else's fake invoice in your name has a better chance of getting through. Many businesses only find out when a customer says they never got the email.
How to fix it
- List every service that sends mail as your domain: your mailbox provider (Microsoft 365, Google Workspace), your website's contact form, your invoicing and marketing tools.
- Publish one TXT record at the root of the domain, for example: v=spf1 include:spf.protection.outlook.com ~all for Microsoft 365, or v=spf1 include:_spf.google.com ~all for Google Workspace, plus an include for each other service that sends for you.
- If you found two v=spf1 records, merge them into one. Two records make both invalid.
If you would rather not touch DNS or server settings yourself, forward this page and your report to whoever manages your website, or ask us to do it.
Keep an eye on it
A one-off check tells you how things stand today. On Starter and up, DomainGuard re-checks the domains it watches every day and alerts you in the app when something important changes, so you hear about it before a customer does.