methodology / Email & Communications / #82

SPF lookup count (10-limit deliverability check)

live factor #82 · Email & Communications · scoring impl: implemented · weight 0.3%

What we measure

SPF has a hard limit of 10 DNS lookups. Going over breaks email delivery silently — Gmail and Outlook just refuse the messages. Most domains that hit this limit don't realize until something stops working.

How to improve your score

Use SPF flattening services (or rewrite includes to direct IPs) to stay under the limit. Tools: spf-record.com, easydmarc.

Data source

Data source for this factor is not yet documented.

Implementation notes

Recursively expand `include:` and `redirect=` directives; count total lookups.

Scoring

Scoring formulas are versioned with the methodology. The current method (v1.1.0) maps raw measurements to pass, warn, fail. Factor weights determine how much each contributes to the composite — see the methodology index for the full table.

Version history

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