Email

Detect whether a domain accepts mail to any mailbox (catch-all)

Sends live SMTP RCPT TO probes with random non-existent mailboxes at the domain's primary MX host and infers catch-all behavior from acceptance/rejection. Use this to avoid false-positive 'valid' verdicts on catch-all domains. Slower than the other email checks (real SMTP round-trips). Rate limit: 20 requests/minute per IP.

post/api/v1/email/catchall

Request

  • Base URL: https://firstsales.io
  • URL: https://firstsales.io/api/v1/email/catchall
  • Auth: none required

Request body

domainstring required

Example request

{
  "domain": "example.com"
}

Response

Catch-all detection result.

isCatchAllboolean required
confidence'high' | 'medium' | 'low' required
scorenumber required

Changes

No recorded changes to this operation across all 1 revision of this API.