SecureMX email service provider (ESP)

According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), SecureMX is the email service provider (ESP) for 609 domains — 0.10% of 617,702 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.

Key facts

SecureMX is a Japanese email service provider (ESP) that organisations use to handle SMTP infrastructure, identifiable through SPF include mechanisms in domain configurations. Its footprint is concentrated among smaller and mid-market websites on .co.jp domains rather than the largest international brands.

For sysadmins, deliverability engineers, and marketers working with email, SecureMX's regional concentration provides useful context: senders targeting Japanese organisations may encounter it in their recipients' SPF records, and anyone mapping the email provider ecosystem should recognise its focus on the smaller-site and Japanese-market segment as a distinct provider tier.

Where SecureMX sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00000.0%
Top 10,00050.8%
Top 100,00010917.9%
Top 1,000,00046977.0%
Unranked264.3%

Top-level domain split

TLDDomainsShare
.co.jp32753.7%
.jp13622.3%
.com7312.0%
.or.jp345.6%
.ac.jp142.3%
.ne.jp81.3%
.net50.8%
.org30.5%
.co.id30.5%
.co.kr10.2%

What SecureMX users also use

Cross-tabulated from the same daily snapshot — the other email services seen on the same 609 domains.

TypeServiceDomainsShare of SecureMX users
MailboxSecureMX (JP)48379.3%
MailboxMicrosoft 365487.9%
MailboxUnknown / Other213.4%
MailboxGoogle Workspace203.3%
MailboxSelf-Hosted162.6%
MailboxProofpoint61.0%
ESPAmazon SES8113.3%
ESPSalesforce6310.3%
ESPRepica WebCAS477.7%
ESPCrmStyle304.9%

Testing and reputation targeting in the Japanese market

SecureMX's presence is almost entirely confined to .co.jp domains and smaller organisations within Japan. This means senders and reputation managers targeting global audiences rarely need to configure specifically for SecureMX, but anyone conducting regional testing in Japan or analysing Japanese email infrastructure should note it as part of the local provider landscape.

See the full SecureMX data page (KPI cards, trend, sample domains) →

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Frequently asked questions

Do I need to configure my SPF records specifically for SecureMX?

Only if you use SecureMX as your outbound mail provider. Standard SPF, DKIM, and DMARC configuration suffices for senders targeting Japanese recipients; you need not configure specifically for SecureMX.

How many domains use SecureMX?

609 domains in the Tranco top-1M use SecureMX as their email service provider (ESP) as of July 13, 2026 (0.10% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.

Is SecureMX common enough to affect email deliverability testing?

SecureMX accounts for 0.10% 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.

Which countries or TLDs use SecureMX most?

SecureMX's largest TLD is .co.jp (53.7% of its domains); it appears across 15 TLDs in total.

Other email service provider (ESP)s

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%)