How to verify an email address
There are four reliable ways to confirm an email address exists — from a manual MX lookup to an automated mailbox check. Use the verifier below for an instant answer, then read the methods to understand what it is doing.
5 of 5 free checks left today — no signup required.
Method 1 — Check the syntax and the domain
Start with the obvious failures: a missing @, an invalid TLD, or a domain with no MX record. Run 'nslookup -type=mx domain.com' — if nothing comes back, the domain cannot receive mail at all and every address on it is invalid.
Method 2 — Run a live mailbox check
Ask the domain's receiving mail server whether it will accept mail for that specific address, without ever delivering a message. The server either accepts the recipient or rejects it as non-existent. Doing this reliably from your own machine is impractical — most networks block the traffic outright — which is why a hosted verifier is used in practice.
Method 3 — Handle catch-all domains correctly
On a catch-all (accept-all) domain the server accepts every address, so a plain acceptance proves nothing about the individual mailbox. Most verifiers hand those back as 'risky' or 'unknown'. VeriMailX resolves them to a definitive valid or invalid instead, still without sending an email.
Method 4 — Verify the whole list automatically
For anything beyond a handful of addresses, upload a CSV and let the engine run every check for you, retries included. You get a clean send file, a suppression list and your original columns preserved.
What not to do
Do not send a test email to check an address — a bounce damages your sender reputation and a silent accept teaches you nothing on a catch-all domain. Do not rely on regex alone, and do not trust a verifier that never returns 'unknown'; honest engines admit when a server refuses to answer.
Frequently asked questions
How do I verify an email address without sending an email?
Resolve the domain's MX records and ask the receiving mail server whether it will accept mail for that address, without ever delivering a message. The server's answer tells you whether the mailbox exists.
Can I verify an email address for free?
Yes. The verifier on this page runs 5 free checks per day with no account.
How do I verify a Gmail address?
Gmail answers mailbox-level queries, so a standard verification returns a definitive valid or invalid result for @gmail.com addresses.
How do I verify thousands of addresses?
Upload a CSV of up to 50,000 rows in the dashboard or call the bulk API endpoint; results come back with per-row status, reason and score.
Verify your whole list
Paste up to 10 addresses in the bulk checker, or create a free account to upload a CSV and use the API.