Free tools
SPF Record Generator
Builds a starter SPF string. Validate with your DNS host. We do not silently query your production DNS. These tools run in your browser. They are educational — not a substitute for mailbox warmup and clean lists.
SPF starter record
v=spf1 include:_spf.google.com include:spf.protection.outlook.com ~all
Paste into DNS only after you confirm which providers actually send for you. Start DMARC at p=none.
How to use this
Builds a starter SPF string. Validate with your DNS host. We do not silently query your production DNS.
Then do the real work in RangeLeads
Authenticate a sending domain, warm mailboxes, import a defensible list, and run a short sequence. A calculator will not fix a burned domain.
FAQ
Is this really free?
Yes. No account required for the calculators.
Do you store what I type?
These widgets run client-side. Do not paste customer PII into a public page if your policy forbids it.
Will this make me land in inbox?
No tool on the public internet can promise that.
Keep reading
Send from inboxes you control
14-day trial · 200 unique contacts · Google, Microsoft, or SMTP.