SMTP Test
Check whether a mail server accepts connections and responds correctly — connectivity only.
This tool never asks for, uses, or stores a mailbox password — it only opens a connection, reads the server's banner, and sends EHLO before disconnecting.
About this tool — and its strict limits
This performs exactly one thing: opens a connection to a mail server, reads its startup banner, sends an EHLO greeting to see its capabilities, then disconnects with QUIT. That's the entire interaction.
This tool never authenticates, never sends a message, and never asks for a mailbox password — there is no field for one anywhere on this page, and no code path in this tool that could accept, transmit, or store one. Only three ports can be tested (25, 465, 587 — the standard SMTP ports), every connection has a strict timeout, and destinations resolving to private or internal addresses are refused, the same protection every other tool on this site that connects to a user-specified destination uses.
What a failed test usually means
A connection refused or timed out result usually means either the mail server genuinely isn't reachable on that port, or a firewall (yours, the server's, or a network in between) is blocking it — this tool can't distinguish which, only that a normal connection attempt didn't succeed.
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