Email list validation

List validation here means classifying every row so you can decide what to send. NexiphorVerifier does not stop at a green syntax check — it probes the mailbox and keeps catch-alls out of Valid.

What each row becomes

  • Valid — SMTP evidence the mailbox exists.
  • Invalid — syntax, domain, MX, or RCPT rejection. Do not send.
  • Risky — accepted without mailbox proof (catch-all, some gateways). Filter or send only with an explicit preset.
  • Unknown — the probe did not finish. Refunded. Not a guess.

After the list is classified

Export presets exist so you do not have to rebuild filters in a spreadsheet. valid_and_safe_catchall is Valid plus higher-confidence catch-alls on reputable hosts — those rows still stay Risky on the record.

Status meanings: Valid vs Invalid vs Risky vs Unknown. Running the file: Bulk email verification. Pricing.