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x402 Format Checker – Email Validation
x402
x402 Format Checker – Email Validation is a paid API for AI agents from x402-test.crewofthecaptain.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).
Validates the format and checksum of an email address, returning validity status, reason, and normalized form, paid per-call via x402 in USDC on Base.
Price / call$0.001
Success—
StatusUnknown
How this service works
Format and checksum validation for IBAN, EU VAT, Polish NIP/REGON/PESEL and email, pay-per-call via x402. Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base.
Output
A JSON object containing: 'type' (always 'email'), 'valid' (boolean indicating whether the email passed format and checksum validation), 'reason' (a string explaining the result, e.g. 'ok' or a description of the error), and 'normalized' (the canonicalized/lowercased email string if valid).
Example use cases
User registration email gate
“Before I create this account, check if the email 'jankowalski@@gmail..com' is valid — I want to catch any formatting errors before saving it to the database.”
Bulk contact list cleanup
“I have an email address 'info@my-company.org' from a lead form — validate it and give me the normalized version so I can add it to our CRM without issues.”
Automated form input sanitization
“Someone just submitted 'Alice.Smith+Newsletter@Example.COM' as their email — is it valid, and what's the canonical normalized version I should store?”
Technical details
Endpoint
POSThttps://x402-test.crewofthecaptain.com/api/validate/email?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need lightweight, pay-per-call email format and checksum validation without committing to a subscription-based email verification service. It is ideal for sporadic validation needs, agentic pipelines processing individual records, or cost-sensitive workflows where $0.001 per check is acceptable. It does not perform live mailbox reachability checks (SMTP ping), so prefer a deliverability-focused API if you need to confirm a mailbox actually exists.
Side effects
- Invalid or malformed input string returns valid:false with a reason describing the specific format error
- Empty or missing 'value' field may return a 400-level error or valid:false
- Payment failure via x402 returns HTTP 402 before validation is attempted
- Strings exceeding 512 characters are rejected per schema maxLength constraint
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| value | string |
Output
Schema · Response
{
"type": "json",
"example": {
"type": "email",
"valid": true,
"reason": "ok",
"normalized": "…"
}
}Tags
x402
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