Outcomes

Every validated email address is assigned a status and an optional sub_status. These fields appear on every result object — single-verify responses, poll results, and webhook payloads all use the same schema.

status values

Value	Meaning
valid	Mailbox confirmed deliverable via SMTP
invalid	Mailbox does not exist or hard-rejected
catch-all	Domain accepts all addresses; deliverability unconfirmable
unknown	Could not determine — DNS failure, transient error, or no SMTP probe data

sub_status values

sub_status provides additional signal within a top-level status. It is an empty string ("") when none of the conditions below apply.

Value	Meaning
disposable	Address belongs to a known disposable / temporary email provider
role_based	Address is a role alias (e.g. admin@, support@, noreply@)
accept_all	Domain is a catch-all — every address appears to succeed
no_dns_entries	No MX records found and DNS did not return a transient error
mailbox_not_found	SMTP server returned 550 or 551 (user unknown)
greylisted	SMTP server returned a 4xx temporary rejection — may be greylisting
mail_server_did_not_respond	DNS resolved but SMTP connection timed out or was refused

Sub-status derivation is first-match: disposable > role_based > accept_all > no_dns_entries > mailbox_not_found > greylisted > mail_server_did_not_respond.

Deliverability guidance

status	Use in mailing list?
valid	Yes
invalid	No — remove from list
catch-all	Use with caution; domain accepts all mail but individual mailboxes may not exist
unknown	Treat with caution; retry later if possible

The full result object

{
  "email":             "alice@example.com",
  "status":            "valid",
  "sub_status":        "",
  "free_email":        false,
  "did_you_mean":      null,
  "account":           "alice",
  "domain":            "example.com",
  "details": {
    "role":          false,
    "disposable":    false,
    "catch_all":     false,
    "mx_found":      true,
    "mx_record":     "mail.example.com",
    "smtp_provider": "Google",
    "smtp_code":     250
  },
  "credits_remaining": 4820,
  "processed_at":      "2025-06-10T14:02:11.432Z"
}

credits_remaining is null for system and demo accounts.