Repica WebCAS email service provider (ESP)
According to Live Direct Marketing's daily Tranco top-1M scan (September 12, 2026), Repica WebCAS is the email service provider (ESP) for 745 domains — 0.12% of 629,828 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.
Key facts
- 745 domains in the Tranco top-1M use Repica WebCAS (0.12% of SPF-publishing domains).
- Snapshot date: 2026-09-12 — recomputed every day.
- Strongest TLD: .jp (34.1% of its domains).
- Most co-used service: Google Workspace.
- Directory category: email service provider.
Why Repica WebCAS appears in this category
Repica WebCAS — Japanese email marketing platform.
We classify it as a email service provider from include: mechanisms in the SPF record matching a maintained provider rule. This is infrastructure attribution from public DNS, not evidence of a direct contract or exclusive use.
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 band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 1 | 0.1% |
| Top 10,000 | 15 | 2.0% |
| Top 100,000 | 133 | 17.9% |
| Top 1,000,000 | 595 | 79.9% |
| Unranked | 1 | 0.1% |
Top-level domain split
| TLD | Domains | Share | |
|---|---|---|---|
| .jp | 254 | 34.1% | |
| .co.jp | 217 | 29.1% | |
| .com | 186 | 25.0% | |
| .or.jp | 26 | 3.5% | |
| .net | 22 | 3.0% | |
| .ne.jp | 11 | 1.5% | |
| .ac.jp | 10 | 1.3% | |
| .coop | 6 | 0.8% | |
| .org | 4 | 0.5% | |
| .info | 1 | 0.1% |
What Repica WebCAS users also use
Cross-tabulated from the same daily snapshot — the other email services seen on the same 745 domains.
| Type | Service | Domains | Share of Repica WebCAS users |
|---|---|---|---|
| Mailbox | Google Workspace | 161 | 21.6% |
| Mailbox | Microsoft 365 | 153 | 20.5% |
| Mailbox | Self-Hosted | 145 | 19.5% |
| Mailbox | Unknown / Other | 104 | 14.0% |
| Mailbox | SecureMX (JP) | 41 | 5.5% |
| Mailbox | Amazon SES (inbound) | 17 | 2.3% |
| ESP | Amazon SES | 163 | 21.9% |
| ESP | Salesforce | 75 | 10.1% |
| ESP | SecureMX | 46 | 6.2% |
| ESP | HDEMS | 45 | 6.0% |
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) →
Run a free inbox-placement test across Gmail, Outlook, Yahoo and more — see exactly where your mail lands and why.
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?
745 domains in the Tranco top-1M use Repica WebCAS as their email service provider (ESP) as of September 12, 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 (34.1% of its domains); it appears across 18 TLDs in total.