esp
According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), Q4 Inc is the email service provider (ESP) for 84 domains — 0.01% of 617,702 SPF-publishing domains. Its strongest TLD is .com (95.2% of its domains). Detection: include: mechanisms in the SPF record.
What else the same 84 domains use — cross-tabulated from the same daily snapshot (2026-07-13).
| Type | Service | Domains | Share of Q4 Inc users |
|---|---|---|---|
| Mailbox | Microsoft 365 | 31 | 36.9% |
| Mailbox | Proofpoint | 12 | 14.3% |
| Mailbox | Google Workspace | 11 | 13.1% |
| Mailbox | Mimecast | 9 | 10.7% |
| Mailbox | Cisco IronPort | 5 | 6.0% |
| Mailbox | Self-Hosted | 4 | 4.8% |
| ESP | Salesforce | 23 | 27.4% |
| ESP | HubSpot | 13 | 15.5% |
| ESP | Mimecast | 12 | 14.3% |
| ESP | Amazon SES | 12 | 14.3% |
84 domains in the Tranco top-1M use Q4 Inc as their email service provider (ESP) as of July 13, 2026, according to Live Direct Marketing's daily DNS scan.
Q4 Inc holds 0.01% of SPF-publishing domains in the Tranco top-1M (snapshot of 2026-07-13). The number is recomputed every day.
The largest email service provider (ESP)s in the same category by Tranco top-1M share are: Amazon SES, SendGrid (Twilio), Mailgun, Zendesk, Mailchimp (as of 2026-07-13).
Amazon SES (6.21%) · SendGrid (Twilio) (4.76%) · Mailgun (4.11%) · Zendesk (3.86%) · Mailchimp (3.69%) · Mandrill (3.36%) · HubSpot (3.18%) · Salesforce (2.62%) · Mailjet (Sinch) (2.13%) · Cloudflare Email Routing (1.80%)
Showing 84 of 84 domains.