About this tool. When an email does not arrive you are left guessing between two very different problems: the address is wrong, or the address is fine and something is stopping your mail. This checks everything that can be established without sending anything: whether the address is formed correctly, whether the domain exists, whether it is set up to receive email at all, whether it is a throwaway provider, and whether it looks like a near-miss of a common one. What it deliberately does NOT do is open a connection to somebody else's mail server to ask whether the mailbox exists. That technique is unreliable (large providers answer identically for real and fake addresses), rude, and gets the prober blocklisted, which would be an odd thing for a service that tells you whether you are on blocklists.
Ten signals decide whether your mail arrives. You just checked one.
An address that accepts mail is not the same as mail that arrives. If your own sending domain is unauthenticated, well-formed addresses still land in spam.
- SPF, DKIM, DMARC, MX and blocklist status, graded A to F in one pass
- Every problem written out in plain English, with the record to publish
- Saved under Reports, so you can re-run it and see what changed
- One domain watched against the blocklists daily
Run the full checkup free
No card, and nothing to cancel.
How to read your address check
- We check the address is well formed, then look up whether its domain can receive mail at all. A domain with no MX records cannot, whatever the address in front of it looks like.
- A valid-looking address on a live domain is not proof the mailbox exists. We never send a message to find out, because a test message to a stranger's mailbox is spam and a probe to their server is rude.
- Disposable and throwaway domains are flagged separately. They accept mail perfectly well and nobody reads it, which is a different problem from an address that bounces.
- A typo in a well-known domain (gnail.com, hotmial.com) is called out rather than silently passed, because it is the single most common reason a real person never gets your mail.
Common problems and how to fix them
The address looks fine but mail still bounces
The mailbox may be full, disabled, or the receiving server may be rejecting you rather than the address. Read the bounce message: it names which of those it is.
The domain has no MX records
It cannot receive mail. Either the address is wrong, or the domain is web-only and its owner uses a different address entirely.
You are checking a list of addresses
Fix the typos and drop the dead domains, but do not treat this as a list-cleaning service. The bigger cause of undelivered mail is usually the sending domain's own authentication, not the recipients.
Common questions.How do you check an email address without sending mail?
We read public DNS for the domain, confirm it publishes MX records that can accept mail, and check the address itself for typos, disposable domains and malformed syntax. We never send a message to the address and never connect to somebody else's mail server to ask whether a mailbox exists.
Can you tell me if a mailbox really exists?
No, and neither can anyone else reliably. Most mail servers deliberately accept mail for every address and reject it later precisely so that mailboxes cannot be enumerated. Anyone claiming certainty is guessing or probing.
What is a disposable email address?
A throwaway address on a domain that exists to accept signup mail nobody intends to read. It is technically valid and practically useless, so we flag it separately from an address that fails.
Why does a typo matter so much?
Because it fails silently. gnail.com and hotmial.com are registered domains that accept mail, so nothing bounces, nobody is told, and the message is simply gone.
Is this a list cleaning tool?
No. It checks one address at a time and tells you what is publicly knowable. If your mail is going missing in volume, the cause is usually your own SPF, DKIM and DMARC rather than the addresses you are sending to.