Free tool
Free email verifier
Check whether an address accepts mail — and see the evidence behind the answer.
How this works
The check opens an SMTP conversation with the mail server responsible for the domain and asks whether it would accept mail for that address. It stops before any message is sent, so nothing reaches the recipient.
The result is one of four: deliverable, undeliverable, risky, or unknown. That last one is the important one — it means the mailbox was never actually tested, usually because the server blocked the probe or DNS failed. Most tools report that case as invalid. It is not the same thing, and the difference costs real customers.
Probes are sent from IP addresses under a managed warmup and pacing schedule, with per-provider limits. That is what keeps results accurate at volume rather than degrading into blocks the moment a list gets large.
Questions, answered.
How do you check if an email address is valid without sending an email?
By opening an SMTP conversation with the domain's mail server and asking whether it would accept mail for that address — then stopping before any message is sent. The recipient never receives anything.
What does "catch-all" mean and why does it matter?
A catch-all domain accepts mail for every address, whether the mailbox exists or not. On such a domain a positive verification proves the domain accepts mail, not that the person exists — so we report it explicitly rather than letting it inflate the score.
What does an "unknown" result mean?
It means the mailbox was never tested. The mail server may have blocked our probe, or DNS may have failed. It is not a soft "undeliverable" — treating it as one is how verification tools quietly delete real customers from real lists.
Is it safe to verify an address this way?
Yes. No mail is sent, nothing appears in the recipient's inbox, and nothing is logged against them. We do meter our own probes carefully so the check does not look like a dictionary attack to the receiving server.
How many addresses can I check for free?
This tool is rate-limited per IP address for a handful of checks a minute. A free account gives you 100 credits every month — enough for 200 verifications — and it renews.