According to Live Direct Marketing's daily Tranco top-1M scan (July 12, 2026), ImprovMX is the email service provider (ESP) for 715 domains — 0.12% of 617,244 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.
ImprovMX is an email forwarding service that allows domain owners to create custom email addresses without operating their own mail server. Users configure ImprovMX as the mail exchanger for their domain, and the service forwards incoming mail to an external inbox provider.
In the Tranco top-1M dataset, ImprovMX is concentrated among smaller domains and .com registrations, indicating adoption by startups and small organisations rather than large enterprises. For email professionals, this distribution matters because ImprovMX-using domains often have inconsistent authentication policies (SPF, DKIM, DMARC), and forwarding can introduce unexpected behaviour in authentication checks and deliverability assessments if not properly configured.
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 0 | 0.0% |
| Top 10,000 | 11 | 1.5% |
| Top 100,000 | 58 | 8.1% |
| Top 1,000,000 | 522 | 73.0% |
| Unranked | 124 | 17.3% |
| TLD | Domains | Share | |
|---|---|---|---|
| .com | 376 | 52.6% | |
| .org | 44 | 6.2% | |
| .net | 43 | 6.0% | |
| .io | 16 | 2.2% | |
| .in | 10 | 1.4% | |
| .dev | 9 | 1.3% | |
| .fr | 8 | 1.1% | |
| .co.uk | 8 | 1.1% | |
| .co | 7 | 1.0% | |
| .app | 7 | 1.0% |
Cross-tabulated from the same daily snapshot — the other email services seen on the same 715 domains.
| Type | Service | Domains | Share of ImprovMX users |
|---|---|---|---|
| Mailbox | ImprovMX (forwarding) | 587 | 82.1% |
| Mailbox | Google Workspace | 68 | 9.5% |
| Mailbox | Microsoft 365 | 8 | 1.1% |
| Mailbox | Self-Hosted | 8 | 1.1% |
| Mailbox | Generic / unmatched (mail.*) | 5 | 0.7% |
| Mailbox | ProtonMail | 4 | 0.6% |
| ESP | Amazon SES | 45 | 6.3% |
| ESP | Mailgun | 41 | 5.7% |
| ESP | SendGrid (Twilio) | 26 | 3.6% |
| ESP | Mailjet (Sinch) | 26 | 3.6% |
When ImprovMX is configured as a domain's mail exchanger, the domain's SPF record typically includes an ImprovMX mechanism to authorise the forwarding. Because ImprovMX users span different technical skill levels, SPF records vary in correctness and completeness across ImprovMX-using domains. Additionally, email forwarding can break DKIM and DMARC alignment if the sending domain hasn't been configured to accommodate third-party forwarding, making diagnostic investigation of deliverability issues more complex.
See the full ImprovMX data page (KPI cards, trend, sample domains) →
ImprovMX is a forwarding service used by small organisations and individuals to receive mail at custom domains. Test against it if your audience includes small businesses using custom domain email; otherwise, focus on larger mainstream providers.
715 domains in the Tranco top-1M use ImprovMX as their email service provider (ESP) as of July 12, 2026 (0.12% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.
ImprovMX accounts for 0.12% of SPF-publishing domains 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.
ImprovMX's largest TLD is .com (52.6% of its domains); it appears across 125 TLDs in total.