According to Live Direct Marketing's daily Tranco top-1M scan (July 12, 2026), Generic / unmatched (mx*.*) is the mailbox provider for 18,198 domains — 2.77% of 658,108 domains with MX records. Detection method: primary MX record (lowest preference).
Generic / unmatched (mx*.*)> represents email infrastructure where a domain's primary MX record does not resolve to a known commercial mailbox provider. This category encompasses self-hosted mail servers, custom infrastructure, and independent email operations that manage their own receiving infrastructure without outsourcing to a branded service.
These domains cluster predominantly in the long tail of smaller websites rather than amongst the largest global brands, spread internationally across many top-level domains with .com dominance, and frequently appear alongside Amazon SES. This pattern reflects organisations that operate self-hosted mail infrastructure for receiving, often paired with external services for sending. For senders, this diversity means recipient filtering policies, reputation systems, and authentication enforcement vary significantly; for email operations teams, it underscores the continued presence of decentralised mail governance beyond the major consolidated providers.
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 24 | 0.1% |
| Top 10,000 | 198 | 1.1% |
| Top 100,000 | 1,767 | 9.7% |
| Top 1,000,000 | 13,331 | 73.3% |
| Unranked | 2,878 | 15.8% |
| TLD | Domains | Share | |
|---|---|---|---|
| .com | 5,636 | 31.0% | |
| .net | 1,163 | 6.4% | |
| .de | 1,139 | 6.3% | |
| .ru | 1,132 | 6.2% | |
| .org | 570 | 3.1% | |
| .nl | 381 | 2.1% | |
| .it | 346 | 1.9% | |
| .pl | 336 | 1.8% | |
| .com.br | 333 | 1.8% | |
| .fr | 329 | 1.8% |
Cross-tabulated from the same daily snapshot — the other email services seen on the same 18,198 domains.
| Type | Service | Domains | Share of Generic / unmatched (mx*.*) users |
|---|---|---|---|
| ESP | Amazon SES | 440 | 2.4% |
| ESP | SendGrid (Twilio) | 365 | 2.0% |
| ESP | Mailchimp | 339 | 1.9% |
| ESP | Mailgun | 322 | 1.8% |
| ESP | Netcore Cloud (Pepipost) | 320 | 1.8% |
| ESP | Mailjet (Sinch) | 279 | 1.5% |
| ESP | Mandrill | 276 | 1.5% |
| ESP | Zendesk | 256 | 1.4% |
| ESP | Brevo (ex-Sendinblue) | 189 | 1.0% |
| ESP | Unisender (RU) | 174 | 1.0% |
Self-hosted mail infrastructure represented by generic MX records exhibits significant variation in how strictly it enforces authentication standards (SPF, DKIM, DMARC), applies reputation filtering, and implements rate-limiting. Unlike centralised mailbox providers that operate standardised systems at scale, each self-hosted server may apply unique policies reflecting its operator's security stance and technical capabilities. Senders cannot assume uniform acceptance criteria across generic domains; instead, they must ensure robust authentication and monitor delivery feedback carefully to identify recipient-specific issues or misconfigurations that might otherwise appear as widespread delivery failures.
See the full Generic / unmatched (mx*.*) data page (KPI cards, trend, sample domains) →
Your recipients operate self-hosted mail infrastructure rather than using a commercial provider, so their filtering rules, reputation systems, and authentication strictness may differ from mainstream services. Ensure your authentication (SPF, DKIM, DMARC) is correctly configured and monitor feedback from these recipients, as infrastructure-specific configurations can affect acceptance.
18,198 domains in the Tranco top-1M use Generic / unmatched (mx*.*) as their mailbox provider as of July 12, 2026 (2.77% of domains with MX records), according to Live Direct Marketing's daily DNS scan.
Generic / unmatched (mx*.*) accounts for 2.77% of domains with MX records in the top 1M. Whether you should seed a test mailbox there depends on how much of your audience it represents — the co-usage table above shows the services it appears alongside most.
Generic / unmatched (mx*.*) is growing — its share moved +0.04 pp over the last 30 days (as of July 12, 2026).
Generic / unmatched (mx*.*)'s largest TLD is .com (31.0% of its domains); it appears across 379 TLDs in total.