What are some good online SPF tools?
While the pros and cons of having an SPF record in DNS are debatable, there are many online tools that are helpful for you to create and test your SPF record should you want to try it out.
The main page on the internet for SPF goodness is: http://www.openspf.org
There you can use the box located under ‘Deploying SPF’ to input your domain, and help create your SPF record.
Once you’ve got that SPF record in your DNS (and let the DNS propagate) you can then check it on this fabulous page:
This will give immediate feedback on validating your SPF record and even testing a mail transaction with your SPF record.
Of course there is always dig. This dig command lets you query for your SPF record:
dig domain.com TXT
You can also send an email to a gmail account to test. Google checks for SPF and puts the results in the email headers:
Received-SPF: neutral (google.com: 123.456.789.10 is neither permitted nor denied by best guess record for domain of firstname.lastname@example.org)