Check whether an address can actually receive mail. Syntax, MX records, a live SMTP check, catch-all, role and disposable detection and a deliverability score, for one address or a whole CSV. Powered by the Mailboxlayer API.
Paste it in. The tool runs four checks in order: whether the address is syntactically valid, whether the domain publishes MX records that can accept mail, whether the mail server accepts that specific mailbox when asked over SMTP, and whether the domain accepts everything regardless. Together those tell you whether mail sent to the address has somewhere to land.
An MX record is the DNS entry that says which server receives mail for a domain. If a domain publishes none, nothing can be delivered there at all, no matter how well formed the address looks. It is the cheapest and most decisive check available, which is why it runs before the SMTP step.
A catch-all domain accepts mail for every possible mailbox rather than only the ones that exist. That makes per-address verification impossible: the server says yes to anything, so a positive result proves nothing. The tool flags catch-all domains explicitly instead of reporting a false pass.
A temporary inbox from a service built to expire, used to get past a sign-up form without handing over a real address. They are valid and deliverable right now and useless to you a week later, so they are flagged separately rather than counted as failures.
An address that belongs to a function rather than a person: info@, support@, sales@, admin@. They are usually real and deliverable, but they tend to reach shared inboxes, attract higher complaint rates and hurt sender reputation, so most senders exclude them from marketing lists.
Mailbox providers judge you on bounce rate. Sending to addresses that do not exist is the fastest way to have your domain filtered into spam for everyone else on the list. Cleaning the list first protects the deliverability of the mail you actually care about.
Yes. Paste a comma-separated list or upload a CSV and every address is checked and returned in one table, with the result of each individual check shown rather than a single pass or fail.
Mailboxlayer is an email verification API from APILayer. It performs syntax, MX, SMTP, catch-all, role and disposable checks and returns a deliverability score as structured JSON. It is the API behind this page, and it has a free tier.
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