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Free browser-only configuration tool

SPF Record Generator

Create a draft SPF TXT record for your domain, or add a sender to a straightforward existing policy. See what needs reviewing before you change DNS.

Build an SPF record carefully

Enter the DNS name used by your sending service for the SPF check. SPF authenticates the SMTP MAIL FROM (or HELO) identity, which might differ from the visible From address.

First use the Email Domain Checker or your DNS provider to inspect the current TXT records. Do not publish a second SPF record.

Confirmed sending services

Only select services that actually send mail using this SPF identity. Receiving mail through a provider alone is not evidence that it is an outbound sender.

Use only provider-documented include domains. Separate multiple values with commas or new lines. Do not paste entire SPF policies here.

Use IP ranges only if you know the actual public outbound sending IPs. The addresses above are fictional examples, not recommended values.

How should the record end?

Neither choice alone guarantees inbox delivery. A receiving system decides how it handles SPF results.

Private by design: Your inputs are processed locally in the browser. We do not transmit this draft to our DNS Worker, store it, or change your DNS records.

How to publish an SPF TXT record safely

Identify the actual outbound sending services and SMTP identities first. Review the existing SPF TXT value in DNS. If a record already exists, update that record rather than adding another v=spf1 value at the same DNS name.

Copy the draft only after reviewing its warnings. In your DNS provider, choose TXT, confirm the record's hostname and paste the proposed value. Providers differ in how they represent the root name: some use @, others use a blank field or the domain itself. Do not blindly use @ for a subdomain.

After publication, confirm the effective SPF TXT value using a separate DNS lookup. Test messages from each legitimate provider and examine authentication results. SPF alone does not establish DMARC alignment or inbox placement.

Limitations and sources

This tool is an SPF proposal composer, not a full SPF evaluator. It neither reads public DNS nor expands nested include policies. Its length check supports only single-string TXT values up to 255 bytes; more complex DNS TXT formatting requires specialist review.

Technical references: RFC 7208, Google Workspace SPF setup, and Microsoft 365 SPF guidance. Providers may change their instructions; verify their current settings before using a preset.