Defaults.Exposed › Stats › Email authentication (SPF, DKIM, DMARC)
How many domains have no email authentication at all?
October 2026 census edition
As of October 12, 2026, 157,320,430 domains (47.3% of the 332 million graded in the Defaults.Exposed census) publish neither SPF (Sender Policy Framework) nor DMARC (Domain-based Message Authentication, Reporting and Conformance), leaving them with no email authentication at all.
Neither SPF nor DMARC: how it is measured
It comes from the cross-check pass, which takes the per-domain results and counts the combinations: domains holding one control but not another, and domains holding a whole set together. Every domain in the census is measured directly and counted once.
This is the cohort with neither SPF nor DMARC: a receiving server has no published record to check their mail against. It is also the cheapest cohort to fix, because the first record takes minutes and moves a domain out of it immediately.
The figure is an absolute count of domains rather than a sample scaled up. A domain the census could not decide on is left out rather than estimated.
It moves when domain owners publish, correct or remove the DNS (Domain Name System) records that authenticate their mail. Every one of those records is free and takes minutes to publish, and together they decide whether someone else can send mail as the domain. The number is recomputed from the raw evidence at every edition. What it cannot tell you is where one particular domain stands: for that, see fix your email authentication.
the full grading methodology · the underlying dataset, published open with the counts behind every percentage. If a figure here disagrees with one elsewhere on the site, the dataset is canonical and we would like to know.
Neither SPF nor DMARC: how to cite it
Please cite Defaults.Exposed and link this page. The citation below carries the date.
Defaults.Exposed, "How many domains have no email authentication at all?" (as of October 12, 2026). https://defaults.exposed/stats/how-many-domains-have-no-email-authentication
Permalink: https://defaults.exposed/stats/how-many-domains-have-no-email-authentication · Machine-readable: /stats/s/no-email-auth.json · Licence: open data
Methodology: how we grade the internet · Source data: census data and downloads. Updated with each census edition.