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Free SMTP / IMAP / POP3 test & MX lookup

Point it at a mail server and see the full handshake: connection, capabilities, STARTTLS & certificate, reverse DNS, and blocklist status. Or look up a domain's MX records and its SPF, DMARC and MTA-STS policy — no signup required.

Lookup SMTP · sendIMAP · retrievePOP3 · retrieveMX · domain lookup Mail server hostname Port 255874652525 Run test

SMTP 25/587/465/2525 · IMAP 143/993 · POP3 110/995 · MX takes a domain and opens no connection.

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Deliver a message, not just a handshake

From (envelope sender) To Username (optional) Password

Credentials are used for this one connection and never stored or logged — the AUTH exchange is redacted in the transcript below. The message body is fixed and identifies itself as a test.

Send test email