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SPF, DKIM and DMARC Record Generator

For domain owners, admins and small businesses whose mail lands in spam or gets spoofed. Build the records your DNS host needs in one go.

FreeRuns in your browserNothing uploadedNo sign-up neededAll 15 tools in the Security Toolbox
Keep this resultSign in to email it to yourself or save it to your profile. The tool itself never needs an account.

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How to use

How to use the SPF, DKIM and DMARC Builder

  1. Enter your domain and tick who sends mail for it.
  2. Add the DKIM selector and paste the public key from your mail provider.
  3. Pick the DMARC policy and the report address.
  4. Add the three TXT records at your DNS host.
Worked example

An example, step by step

You enter

example.com sending through Google Workspace, DKIM selector google, DMARC p=none with reports to dmarc-reports@example.com

The tool shows

SPF v=spf1 include:_spf.google.com ~all at @, DKIM at google._domainkey waiting for your public key, and DMARC v=DMARC1; p=none; rua=mailto:dmarc-reports@example.com at _dmarc

FAQ

Questions about the SPF, DKIM and DMARC Builder

Can a domain have two SPF records?

No. Two SPF records make SPF fail. Merge every sender into one record, as this builder does.

Which DMARC policy should I start with?

Start with p=none to collect reports, then move to quarantine and reject once all your real mail passes SPF or DKIM.

What is the SPF 10 lookup limit?

SPF may trigger at most 10 DNS lookups (include, a, mx and nested includes). Above that SPF fails, so remove senders you do not use.

Is the SPF, DKIM and DMARC Builder free and private?

Yes. It is free, needs no sign-up and runs entirely in your browser, so what you type is not uploaded. You only sign in if you want to email a result to yourself or save it to your CareerByteCode profile.

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