Validate an Email - Relaybase

Validate a single email address using Relaybase.

Request

POST https://api.tryrelaybase.com/v1/email/single-validate
Authorization: Bearer rb_key_<token>
Content-Type: application/json

{
  "email": "user@example.com",
  "mode": "medium"
}

{
  "email": "user@example.com"
}

Body parameters

Field	Type	Required	Description
`email`	string	Yes	The email address to validate
`mode`	string	No	Validation depth: `fast`, `medium`, or `deep`. Lighter modes return faster; deeper modes run more thorough checks, including SMTP verification.

Field	Type	Required	Description
`email`	string	Yes	The email address to validate

Response

{
  "data": {
    "catch_all": false,
    "is_disposable": false,
    "is_free": true,
    "is_role_based": false,
    "is_valid": true,
    "mx_valid": true,
    "reason": "Mailbox verified via SMTP",
    "result": "jane@company.com",
    "score": 85,
    "smtp_code": 250,
    "status": "valid",
    "suggestion": "Email appears fully deliverable",
    "syntax_valid": true
  },
  "message": "result",
  "status": 200,
  "success": true
}

See Validation Results for what each field in data means, and how status and score relate to each other.

This endpoint is designed for individual validation requests. Don’t loop over a list of emails with sequential calls — see Rate Limits.