SPF Flattening Tool

Flatten your SPF record to stay under the 10 DNS lookup limit and prevent email delivery issues

What is SPF Flattening?

SPF (Sender Policy Framework) flattening is the process of converting all include: mechanisms in your SPF record into their corresponding IP addresses. This helps you stay within the 10 DNS lookup limit.

Why Flatten Your SPF Record?

  • DNS Lookup Limit: SPF has a hard limit of 10 DNS lookups. Each include: and a mechanism counts as a lookup.
  • Email Delivery: If your SPF record exceeds 10 lookups, it will fail validation and emails may be rejected.
  • Performance: Flattened records reduce DNS resolution time for receiving mail servers.
  • Reliability: Direct IP addresses are more stable than relying on multiple includes.

How It Works

  1. Tool retrieves your current SPF record from DNS
  2. Recursively resolves all include: mechanisms
  3. Extracts all IP addresses (IPv4 and IPv6)
  4. Generates a flattened record with ip4: and ip6: mechanisms
  5. Maintains your original qualifiers (~all, -all, etc.)
Warning: Flattened SPF records need to be updated regularly (monthly recommended) as email providers may change their IP addresses. Consider using automated SPF management tools for production environments.

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SPF Lookup SPF Generator Domain Health Check DMARC Lookup

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