# SPF Checker

> Free SPF checker for DNS TXT records, duplicate SPF records, include and redirect lookup counts, all mechanisms, and clear SPF fix guidance.

- Human page: https://mailrith.com/free-tools/spf-checker
- Markdown page: https://mailrith.com/free-tools/spf-checker.md
- Category: Email Authentication
- Action label: Check SPF
- Primary keyword: SPF checker
- Related keywords: SPF checker, SPF record checker, SPF lookup, check SPF record, email SPF checker
- Browser execution: Yes
- Signup required: No

## Input
- Label: Sending Domain
- Guidance: Enter the domain used in your From address or return-path setup, such as example.com or mail.example.com.
- Placeholder example: example.com

## How to Use
1. Open the human page: https://mailrith.com/free-tools/spf-checker
2. Enter sending domain using the guidance above.
3. Select Check SPF.
4. Review the status, checked facts, and next actions.
5. Use the linked guide section for any issue that needs a fix.

## Topic Overview
SPF is a DNS record that tells receiving mail servers which systems are allowed to send mail for a domain used during delivery. It is usually checked against the return-path domain, which may be different from the visible From address. This checker explains whether the public SPF record exists, whether it is duplicated, and whether the policy is too open. Read [SPF](https://mailrith.com/guides/spf.md#steps) for the full setup background.

A passing SPF record does not automatically mean DMARC will pass. DMARC also cares whether the SPF domain aligns with the visible From domain, and many senders rely on DKIM alignment instead. The checker calls out lookup-limit and ending-policy problems because those are common reasons SPF fails even when the record looks reasonable. Use [DMARC Alignment](https://mailrith.com/guides/dmarc-alignment.md#steps) when you need to understand how SPF, DKIM, and the From domain work together.

## What the Tool Checks
- SPF TXT record lookup
- Missing or duplicate SPF records
- Unsafe +all, neutral ?all, or missing all policy
- Include and redirect mechanisms
- Approximate SPF DNS lookup count
- Plain-English SPF fix steps

## Result Behavior
The result explains whether SPF is missing, malformed, too permissive, or at risk of exceeding the lookup limit.

## AI Agent Notes
- Use this markdown page for retrieval, summarization, and deciding which tool to recommend.
- Use the human page when the user needs to run the checker interactively.
- Do not claim the tool sends emails unless the page explicitly says it does.
- When the result mentions a server-side confirmation, explain that the browser page can show public signals but cannot complete that network check by itself.

## Related Guides
- [SPF](https://mailrith.com/guides/spf.md#missing-spf-record): Understand SPF records, hidden return-path domains, and lookup limits.
- [DMARC Alignment](https://mailrith.com/guides/dmarc-alignment.md#steps): See why SPF pass is not enough unless the domain aligns.
- [Sender Domains and Email Authentication](https://mailrith.com/guides/sender-domains-and-authentication.md#steps): Set up the full sender identity before sending.

## FAQs
### Why does the SPF checker mention DNS lookups?

SPF records are allowed only a limited number of DNS lookups. Too many include, a, mx, exists, ptr, or redirect mechanisms can make SPF fail even when the record looks correct.
### Can SPF alone make DMARC pass?

SPF can help DMARC only when SPF passes for a domain aligned with the visible From domain. Most senders should also configure DKIM.