Google and Microsoft run 30.0% of mail-operating domains with a named provider
Each named provider's share of the mail-operating domains the catalog attributes to a provider, and what the domains it hosts ask receivers to do with mail that fails authentication. The domains no named provider serves are described on their own below.
The domains no named provider serves
32.7M mail-operating domains, 17.4% of all of them, have a primary MX the catalog does not attribute to a named provider. They are left out of the ranking above because they are not one provider or a few: they are what remains once every cataloged provider has been matched, and a single bar for them would read as the largest provider on the list.
Most of them are not on a provider at all: 80.31% have a primary MX named under the domain itself, such as mail.example.com, and 6.85% have a primary MX that cannot take mail. The 12.63% on a third-party MX domain are a long tail rather than a gap in the catalog: they are spread across 438,151 MX domains, and the 1,000 largest of those serve 2.08% of all the domains with no named provider.
Sized by how many domains each of those MX domains serves, 45.87% of the third-party share sits behind ones serving 100 or more, 33.85% behind ones serving 10 to 99, and 20.28% behind ones serving fewer than ten. The largest serves 5,058 domains, so there is no missing provider of any size to find: cataloguing further names the tail one small operator at a time.
They publish SPF at 80.8% against 77.9% for the named providers together, DMARC at 36.9% against 40.4%, and enforce DMARC at 13.3% against 14.1%.
SPF, DMARC and enforcement: domains with no named provider against the named providers
| Population | Domains | SPF | DMARC | Enforcing | p=none of publishers |
|---|---|---|---|---|---|
| No named provider (uncataloged) | 32.7M | 80.8% | 36.9% | 13.3% | 63.8% |
| Named providers, together | 125.1M | 77.9% | 40.4% | 14.1% | 65.1% |
What the remainder is made of
The mail-operating domains no named provider serves, by their primary MX. Free to quote with attribution; open the notes on a card before you do.
Mail-operating domains with no named provider whose primary MX is under their own domain
26,293,212 of 32.7M mail-operating domains with no named provider
Source: Datazag · as of 2026-09-24
Mail-operating domains with no named provider whose primary MX is a third-party domain the catalog does not name
4,134,106 of 32.7M mail-operating domains with no named provider
Source: Datazag · as of 2026-09-24
Mail-operating domains with no named provider whose primary MX cannot take mail
2,241,128 of 32.7M mail-operating domains with no named provider
Source: Datazag · as of 2026-09-24
Third-party MX domains serving mail-operating domains with no named provider
438,151 of across Datazag corpus measurement over gold.dns_wide: primary MX resolved to its registrable domain through lake.ref.public_suffix and matched against lake.ref.provider_catalog
Source: Datazag · as of 2026-09-24
Mail-operating domains with no named provider served by the 1,000 largest uncataloged MX domains
680,912 of 32.7M mail-operating domains with no named provider
Source: Datazag · as of 2026-09-24
Domains on a third-party MX serving 100 or more of them
1,896,303 of 4.1M mail-operating domains with no named provider on a third-party MX
Source: Datazag · as of 2026-09-24
Domains on a third-party MX serving 10 to 99 of them
1,399,221 of 4.1M mail-operating domains with no named provider on a third-party MX
Source: Datazag · as of 2026-09-24
Domains on a third-party MX serving fewer than 10 of them
838,582 of 4.1M mail-operating domains with no named provider on a third-party MX
Source: Datazag · as of 2026-09-24
Domains served by the largest uncataloged third-party MX domain
5,058 of across Datazag corpus measurement over gold.dns_wide: primary MX resolved to its registrable domain through lake.ref.public_suffix and matched against lake.ref.provider_catalog
Source: Datazag · as of 2026-09-24
Providers enforce at similar rates
Enforcement spans only 29 points across the 30 largest providers, so provider defaults are not where the variation is.
DMARC publication and enforcement by mail provider
| Mail provider | Domains | Publishes DMARC | Enforces | Gap |
|---|---|---|---|---|
| 22,173,653 | 32.72% | 13.66% | 19.1pp | |
| Microsoft | 15,375,493 | 39.86% | 22.02% | 17.8pp |
| IONOS | 13,268,525 | 93.65% | 29.01% | 64.6pp |
| GoDaddy | 10,920,182 | 13.94% | 12.07% | 1.9pp |
| Namecheap | 10,261,793 | 12.41% | 0.69% | 11.7pp |
| Hostinger | 4,695,637 | 85.39% | 1.06% | 84.3pp |
| OVHcloud | 3,288,115 | 9.82% | 2.83% | 7.0pp |
| Cloudflare | 2,581,299 | 28.27% | 9.29% | 19.0pp |
| Zoho | 2,176,854 | 36.04% | 12.37% | 23.7pp |
| OpenSRS | 1,868,307 | 44.42% | 1.27% | 43.2pp |
| Proofpoint | 1,680,745 | 38.31% | 27.08% | 11.2pp |
| All-inkl.com | 1,573,251 | 51.34% | 1.09% | 50.2pp |
| Aruba.it | 1,515,618 | 77.09% | 0.55% | 76.5pp |
| SiteGround | 1,286,510 | 96.26% | 1.58% | 94.7pp |
| Yandex | 1,198,299 | 7.85% | 2.72% | 5.1pp |
| QSC AG | 1,005,818 | 4.13% | 1.33% | 2.8pp |
| one.com | 903,737 | 9.83% | 5.35% | 4.5pp |
| Tencent | 862,247 | 16.25% | 3.11% | 13.1pp |
| Xserver | 850,976 | 10.49% | 3.07% | 7.4pp |
| Titan | 832,635 | 29.40% | 1.92% | 27.5pp |
| Host Europe | 826,167 | 2.61% | 0.96% | 1.7pp |
| Hetzner Online | 815,245 | 21.62% | 8.07% | 13.5pp |
| Beget | 739,113 | 2.28% | 0.48% | 1.8pp |
| gandi.net | 737,765 | 8.82% | 4.05% | 4.8pp |
| Amazon AWS | 736,215 | 29.01% | 14.13% | 14.9pp |
| Bluehost | 710,624 | 12.97% | 0.86% | 12.1pp |
| Mailgun | 634,638 | 28.59% | 12.60% | 16.0pp |
| 20i | 633,015 | 16.60% | 2.14% | 14.5pp |
| Alibaba | 627,674 | 8.37% | 2.85% | 5.5pp |
| Porkbun | 592,454 | 9.06% | 5.12% | 3.9pp |
Query these statistics directly
Every figure on this page is served as Parquet. Same format as the corpus itself.
SELECT * FROM read_parquet('https://observatory.datazag.com/observatory_statistics.parquet');