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← Email security

Free SPF record builder

Tick the boxes for the email services you actually use. We build the TXT record and count DNS lookups so you never blow past the RFC 7208 10-lookup limit.

1. Pick your senders

Mailbox providers

Transactional

Marketing & CRM

2. Custom mechanisms (optional)

3. Default policy

Start with ~all while you confirm the senders are right. Once aligned, tighten to -all. +all authorizes every server on the internet — never use it.

Your SPF record

0 / 10 DNS lookups
v=spf1 -all
Token breakdown
  • -allHard-fail — reject unauthorized senders.
Where to publishAdd this as a TXT record at the apex of your domain (or the subdomain you actually send mail from). Most DNS providers (Route 53, Cloudflare, Google Domains) accept the value verbatim. After publishing, wait 5–60 minutes and confirm with the free email security scan.

Want to know when your SPF actually breaks? Continuous monitoring rescans your domain on a schedule and emails / Slacks / webhooks you the moment a record drifts — including SPF blowing the lookup limit.

See pricing →

Keep hardening your email

Each record is one layer. Check the rest of yours — every tool is free, no account.

Scan all 8 at once →

Email security scan

Run all 8 checks at once

SPF analyzer

Count your real DNS lookups

DMARC generator

Build a v=DMARC1 record

DMARC validator

Grade a record you have

DMARC report analyzer

Read a rua= XML report

DKIM validator

Check a DKIM key

Header analyzer

Trace a suspicious email

Blocklist checker

Are you on a DNSBL?

BIMI check

Get your logo in inboxes

MTA-STS

Force TLS on inbound mail

TLS-RPT

Get TLS failure reports

DMARC visibility

Ingest your rua= reports

Continuous monitoring

Catch record drift on a schedule