Defaults.Exposed › September 2026 census › v10 registry › MX records
MX records
Methodology v10 · canonical ID mx-record · Email Security · scored · census as of September 5, 2026
Whether your domain is correctly set up to receive email at all.
Definition
| Canonical ID | mx-record |
|---|---|
| Category | Email Security |
| Grade impact | Scored, counts toward the grade |
| Pass | The domain publishes at least one resolvable MX record. |
| Fail | No MX records are published (mail to the domain cannot be routed normally). |
| Example (passing) | example.com. 3600 IN MX 10 mail.example.com. |
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
54.7% of graded domains publish at least one MX record (173,282,307 of 316,600,902, as of September 5, 2026).
Census denominator: 316,600,902 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/fix/mx
Cite this check
Defaults.Exposed, "MX records (mx-record)", Grading Methodology v10 (census as of September 5, 2026). https://defaults.exposed/methodology/mx-record
Permalink: https://defaults.exposed/methodology/mx-record ·
All 34 checks: v10 registry ·
Machine-readable: /methodology/checks.json ·
Licence: open data