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Free local SPF tool

Build an SPF policy without hiding what cannot be simulated.

Start fresh or load a current TXT value, preserve its order, edit every supported mechanism with an explicit qualifier, and review lookup limits and the exact DNS diff before export.

  • One ordered policy

    Add IPv4, IPv6, include, a, mx, exists, redirect, and all terms in their real evaluation order.

  • Conservative editing

    Untouched imported terms round-trip exactly, while every change appears in a before-and-after diff.

  • No hidden DNS calls

    The editor is local and labels lookup estimates that cannot be known without resolving DNS.

Paste one concatenated TXT value, without DNS-zone quotes. Loading never resolves DNS or sends the record anywhere.

Guided policy order

Authorization terms

SPF evaluates mechanisms from left to right. Every editable mechanism shows its qualifier explicitly; imported raw spelling is retained until that term is changed.

The policy has no terms yet

Add only known sending sources, then choose an explicit all result after reviewing real mail evidence.

Before and after

Before

No existing record loaded

After

v=spf1

Removed terms

None

Added terms

None

Structural findings

  • NoteSPF.TERMINAL.IMPLICIT_NEUTRAL

    The SPF record relies on the implicit neutral result

    An explicit all mechanism or redirect modifier makes the intended default easier to diagnose.

  • BlockingSPF.BUILDER.EMPTY_POLICY

    Add at least one policy term

    A bare v=spf1 value falls through to implicit neutral and does not describe an intentional sending policy.

What this local editor cannot prove

  • No DNS queries are made by this editor. Recursive include and redirect costs are not known until they are resolved.
  • Void lookups are DNS outcomes and cannot be predicted from record text alone.
  • An SPF pass or fail also requires the connecting IP, MAIL FROM identity, and HELO identity.

This is not an SPF pass/fail simulation. A real result needs the connecting IP, MAIL FROM identity, and HELO identity.