According to Live Direct Marketing's daily Tranco top-1M scan (July 12, 2026), Paubox is the email service provider (ESP) for 165 domains — 0.03% of 617,244 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.
Paubox is an email service provider that appears within email authentication records across the public web, identifiable through its SPF include mechanisms in domain DNS configurations.
Paubox's footprint skews toward smaller and mid-market organisations rather than the largest global brands, concentrating heavily within the .com namespace. The provider appears particularly often alongside Google Workspace, suggesting a complementary role within organisations that have already committed to modern cloud email platforms. For email professionals, this pattern signals that any infrastructure audit of a site receiving mail from a Paubox-aligned domain should account for the provider's presence in the sending ecosystem.
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 0 | 0.0% |
| Top 10,000 | 0 | 0.0% |
| Top 100,000 | 21 | 12.7% |
| Top 1,000,000 | 129 | 78.2% |
| Unranked | 15 | 9.1% |
| TLD | Domains | Share | |
|---|---|---|---|
| .com | 127 | 77.0% | |
| .org | 19 | 11.5% | |
| .ai | 5 | 3.0% | |
| .net | 4 | 2.4% | |
| .health | 2 | 1.2% | |
| .io | 2 | 1.2% | |
| .vc | 1 | 0.6% | |
| .law | 1 | 0.6% | |
| .md | 1 | 0.6% | |
| .edu | 1 | 0.6% |
Cross-tabulated from the same daily snapshot — the other email services seen on the same 165 domains.
| Type | Service | Domains | Share of Paubox users |
|---|---|---|---|
| Mailbox | Google Workspace | 68 | 41.2% |
| Mailbox | Microsoft 365 | 46 | 27.9% |
| Mailbox | Generic / unmatched (mx*.*) | 11 | 6.7% |
| Mailbox | Proofpoint | 11 | 6.7% |
| Mailbox | Mimecast | 6 | 3.6% |
| Mailbox | Unknown / Other | 6 | 3.6% |
| ESP | HubSpot | 42 | 25.5% |
| ESP | Salesforce | 38 | 23.0% |
| ESP | Zendesk | 26 | 15.8% |
| ESP | Amazon SES | 22 | 13.3% |
When Paubox appears in an organisation's SPF record, it adds an additional authorised sender range to the domain's authentication posture. This is common practice for companies layering multiple email services atop their primary platform—often Google Workspace. When testing email authentication or diagnosing delivery issues, the presence of Paubox includes means that SPF validation will check against Paubox's published sender IP ranges in addition to the primary email provider's, and overlooking any included provider can result in false-positive SPF failures or incomplete authentication checks.
See the full Paubox data page (KPI cards, trend, sample domains) →
Paubox is an email service provider authorised to send on behalf of that domain; when present in an SPF record, mail from Paubox IP ranges will pass SPF checks. If you are auditing delivery or authentication, verify that all SPF includes—including Paubox—are intentional and still in use.
165 domains in the Tranco top-1M use Paubox as their email service provider (ESP) as of July 12, 2026 (0.03% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.
Paubox accounts for 0.03% 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.
Paubox's largest TLD is .com (77.0% of its domains); it appears across 12 TLDs in total.