Public email posture
How well-known domains authenticate their email.
Each report reads public DNS for one domain — DMARC policy via the RFC 9989 tree walk, SPF and its lookup cost, MX routing, DKIM selectors, MTA-STS — grades the result, and records every change. 3 domains are currently published; more are added as they accumulate history.
A: 1B: 2C: 0D: 0F: 0
| Domain | Rank | Grade | DMARC | Snapshots | Checked |
|---|---|---|---|---|---|
| cloudflare.com | — | A | reject | 1 | 2026-09-09 |
| github.com | — | B | quarantine | 1 | 2026-09-09 |
| wikipedia.org | — | B | reject | 1 | 2026-09-09 |
Grades summarize DMARC enforcement and SPF strictness only. They describe the public control plane, not deliverability or organizational security. Domain owners can request a correction or removal through the contact form. Check any domain now with the Bulk DMARC & SPF Checker.