Check email format and MX records
The MailDrop email validator checks whether an email address is properly formed and whether its domain is actually set up to receive mail. Type or paste an address and the tool performs two checks: a syntax test against standard RFC formatting rules, and a live DNS lookup of the domain's MX records performed on our server. The results show you at a glance whether the address could plausibly work.
Syntax alone does not tell the whole story. An address like [email protected] can pass every formatting rule and still be undeliverable because the domain has no mail servers behind it. The MX record lookup closes that gap by querying DNS for the hosts that accept mail for the domain, and the tool displays each mail server host together with its priority in a clear table, so you can see exactly where messages for that domain would be routed.
The validator never sends an email and never contacts the recipient's mail server, so it cannot confirm that a specific mailbox exists, and the address owner is never alerted. It is free, requires no registration, and pairs naturally with MailDrop temporary email when you are testing signup forms and mail flows.
Type or paste the address you want to check into the input field. Full addresses work best, since the tool needs both the local part before the @ sign and the domain after it to run its checks.
Submit the address and the tool first verifies the syntax against RFC formatting rules, catching missing @ signs, illegal characters, bad dots, and malformed domains before any network lookup happens.
If the syntax is valid, the server queries DNS for the domain's MX records. A table lists each mail server host and its priority, where lower numbers indicate the servers tried first.
Valid syntax plus at least one MX record means the domain can receive mail. No MX records is a strong sign the address is dead. Remember the tool cannot confirm the individual mailbox exists.
No. The validator only inspects the address format and performs a DNS lookup for the domain's MX records. It never connects to the recipient's mail server, never sends a message, and never triggers any notification. The owner of the address has no way of knowing a check took place.
Not with certainty. The tool confirms that the address is well formed and that the domain publishes mail servers willing to accept messages. Whether the specific mailbox before the @ sign exists is something only the receiving server knows, and many servers deliberately hide that information to block address harvesting.
MX, or mail exchanger, records are DNS entries that name the servers responsible for accepting email for a domain. Each record carries a priority, and sending servers try the lowest number first. A domain with no MX records usually cannot receive mail, so their presence is a practical deliverability signal.
Correct formatting only means the address follows the rules for how addresses are written. If the domain does not exist, has expired, or publishes no MX records, mail cannot be delivered no matter how clean the syntax is. That combination of passing syntax and failing DNS is exactly what this tool is designed to reveal.
When you build or test a signup flow, you can validate the addresses your form collects here and use a MailDrop disposable email inbox as the receiving end. That lets you exercise the whole pipeline, from format checking to actual delivery, without exposing a personal address or polluting a real mailbox with test messages.