Repica WebCAS email service provider (ESP)

According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), Repica WebCAS is the email service provider (ESP) for 728 domains — 0.12% of 617,702 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.

Key facts

Repica WebCAS is a Japanese email service provider operated by Repica Corporation, serving smaller and mid-market organisations across Asia-Pacific and beyond. It provides email infrastructure for transactional messaging, campaign distribution, and mailbox services primarily to clients in Japan and neighbouring regions.

Its footprint in global email infrastructure is modest and concentrated: it appears predominantly in the long tail of smaller websites rather than major brands, with a geographic concentration in Japan across multiple TLDs. Organisations encountering Repica WebCAS SPF records—particularly when Japan-based senders pair it with Google Workspace—should recognise it as a supplementary mail pathway rather than a primary inbox or bulk-mail platform for most recipient bases.

Where Repica WebCAS sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00010.1%
Top 10,000141.9%
Top 100,00013218.1%
Top 1,000,00053573.5%
Unranked466.3%

Top-level domain split

TLDDomainsShare
.jp24233.2%
.co.jp21028.8%
.com19426.6%
.or.jp253.4%
.net223.0%
.ne.jp111.5%
.ac.jp81.1%
.coop60.8%
.org40.5%
.tokyo10.1%

What Repica WebCAS users also use

Cross-tabulated from the same daily snapshot — the other email services seen on the same 728 domains.

TypeServiceDomainsShare of Repica WebCAS users
MailboxGoogle Workspace15421.2%
MailboxSelf-Hosted14620.1%
MailboxMicrosoft 36514219.5%
MailboxUnknown / Other10814.8%
MailboxSecureMX (JP)405.5%
MailboxAmazon WorkMail152.1%
ESPAmazon SES16222.3%
ESPSalesforce679.2%
ESPFSI Email Security476.5%
ESPSecureMX476.5%

SPF Detection and Repica's Distributed, Long-Tail Presence

Repica WebCAS manifests in email infrastructure primarily through SPF include mechanisms, indicating its role as an authorised outbound mail handler for smaller organisations. Its scattered international footprint, dominated by Japan and spread across numerous TLDs, means recipient systems encounter it infrequently in high-volume mail flows. For deliverability practitioners, Repica's minimal visibility in major ISP complaint and abuse-report streams reflects both its smaller clientele and its typical role as a supplementary service—often deployed alongside cloud suites like Google Workspace rather than as a standalone mail backbone.

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

Are your emails landing in spam?
Run a free inbox-placement test across Gmail, Outlook, Yahoo and more — see exactly where your mail lands and why.
Test inbox placement →

Frequently asked questions

Why do I see Repica WebCAS in SPF records?

Repica WebCAS appears in SPF includes as an authorised outbound mail handler, indicating the sender organisation (typically a smaller Japanese firm) uses Repica's platform for email delivery and campaign infrastructure. It is often deployed alongside other cloud services such as Google Workspace.

How many domains use Repica WebCAS?

728 domains in the Tranco top-1M use Repica WebCAS as their email service provider (ESP) as of July 13, 2026 (0.12% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.

Is Repica WebCAS common enough to affect email deliverability testing?

Repica WebCAS 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.

Which countries or TLDs use Repica WebCAS most?

Repica WebCAS's largest TLD is .jp (33.2% 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%)