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x-402 Email Address Verifier
x402
x-402 Email Address Verifier is a paid API for AI agents from api.x-402.online, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-02).
Validates an email address through five DNS-based checks (syntax, MX, SPF, DMARC, disposable domain, role address) and returns a deliverability rating of NO, RISKY, or LIKELY — without sending any message or opening an SMTP session.
Price / call$0.005
Success—
StatusUnknown
How this service works
Check whether an email address is well-formed and its domain can receive mail, before you send. Five DNS checks on an email address, no message sent: syntax, MX presence and hosts, SPF record, DMARC policy, disposable domain, role address. Returns deliverable as NO, RISKY or LIKELY. It does not open an SMTP session and says so: mailbox existence is explicitly not c…
Output
Returns a deliverability verdict of NO, RISKY, or LIKELY along with individual check results covering: email syntax validity, MX record presence and hostnames, SPF record content, DMARC policy, whether the domain is a known disposable provider, and whether the local part is a role address (e.g. info@, admin@). Mailbox existence is explicitly not checked — no SMTP session is opened.
Example use cases
Pre-send lead list validation
“I've got a new lead with the email address sales-lead@somecompany.io — can you verify whether that email address is actually deliverable before I reach out? Check the DNS records, SPF, DMARC, and flag it if it looks disposable or is a role address.”
Sign-up form abuse prevention
“Someone just signed up with the email noreply@mailinator.com — can you check whether that's a real, deliverable address or a throwaway? I need to know if it's risky or not before I create the account.”
CRM data hygiene check
“I need to validate the email address contact@oldcompany.net in my CRM — run all five DNS checks on it and tell me if it's likely to be deliverable, risky, or not deliverable at all.”
Technical details
Endpoint
GEThttps://api.x-402.online/v1/email/verify?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need a fast, privacy-safe email pre-validation that doesn't send any message or require SMTP access. Ideal for lead qualification, sign-up form gating, CRM hygiene, and mailing list scrubbing where you want DNS-level confidence (syntax + MX + SPF + DMARC + disposable + role checks) without touching the recipient's inbox. Prefer it over full SMTP verification when avoiding false deliveries or GDPR-sensitive probe messages is important.
Side effects
- Invalid or malformed email input returns a syntax error without DNS checks
- DNS lookup timeout may prevent MX/SPF/DMARC results from being returned
- Private or internal domains may return no MX/SPF/DMARC records even for valid addresses
- Payment failure (402) if USDC balance is insufficient
- Rate limiting if too many requests are made in quick succession
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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