Defaults.Exposed › Methodology › v7 registry › SPF policy strength
SPF policy strength
Methodology v7 · canonical ID spf-policy-strength · Email Security · scored · census as of July 28, 2026
A weak SPF only warns; a strict one actually blocks forgeries.
Definition
| Canonical ID | spf-policy-strength |
|---|---|
| Category | Email Security |
| Grade impact | Scored — counts toward the grade |
| Pass | The SPF record ends in a hardfail all-mechanism (-all), telling receivers to reject unauthorized senders. |
| Fail | The record ends in ~all (softfail), ?all (neutral), or +all (permits anyone), or no SPF exists. |
| Example (passing) | v=spf1 include:_spf.example-mailer.com -all |
No-data rule: when this check couldn't be determined for a domain (timeout, SERVFAIL, redacted
source) it returns N/A and is excluded from that domain's scoring denominator — "couldn't determine"
is never counted as a failure. "Determined absent" is a real fail.
Prevalence across the census
20.1% of graded domains publish SPF with a hardfail (-all) policy (55,335,121 of 275,666,275, as of July 28, 2026).
Softfail (~all) records count toward SPF presence but not full policy strength.
Census denominator: 275,666,275 graded domains. Aggregates only — never an individual domain's result.
Fix it
Plain-English impact, cost of ignoring it, and step-by-step remediation: defaults.exposed/en/fix/spf
Cite this check
Defaults.Exposed, "SPF policy strength (spf-policy-strength)", Grading Methodology v7 (census as of July 28, 2026). https://defaults.exposed/methodology/v7/spf-policy-strength
Permalink: https://defaults.exposed/methodology/v7/spf-policy-strength ·
All 34 checks: v7 registry ·
Machine-readable: checks.json ·
Licence: open data