Email Deliverability Tester

This tool combines everything the format validator checks with a live MX record lookup, producing a single deliverability score and a plain checklist of what passed and what didn't for one address.

Format checks run locally; the MX check queries a public DNS resolver in real time.

What's included in the score

This tester runs four checks in sequence: whether the address matches valid email syntax, whether the domain is on a known disposable-provider list, whether the local part looks like a shared role inbox rather than a person, and — the check that sets it apart from the plain validator — a live DNS lookup to confirm the domain actually has MX records configured, meaning it's technically capable of receiving mail at all.

Each check contributes to a percentage score, and you get a full breakdown showing exactly which checks passed. This is the most complete picture this site's client-side tools can offer without actually attempting delivery — it stops short of an SMTP handshake, which is the only way to get closer to confirming a specific mailbox (not just the domain) will accept a message.

Why domain checks matter more than they seem

It's common to assume that if an email address is formatted correctly, it will work — but a surprising number of addresses fail simply because the domain itself has no mail server configured (a typo'd domain, an expired domain, or a website-only domain that was never set up to handle email). Catching that with a live MX check before sending saves a wasted send attempt and, on a larger scale, protects your sending reputation from unnecessary bounces.

Best practices

For anything beyond a single ad-hoc check — say, validating an entire list before an important campaign — run the Bulk Email List Checker first to catch obvious format issues at scale, then spot-check a handful of individual addresses here for the added confidence of a live MX confirmation.

Frequently asked questions

Does a 100% score guarantee the email will be delivered?

No. Even with valid format, a real domain and active MX records, an individual mailbox could still be full, deleted, or set to reject specific senders — none of which can be detected without an actual send attempt.

How is this different from the plain Email Validator?

The Email Validator checks format and known-domain patterns only. This tool adds a live MX record lookup on top, confirming the domain is actually configured to receive mail — a stronger, more complete signal.

Why would the MX check show 'unknown'?

If the DNS lookup request fails — due to a network issue on your end or the resolver being temporarily unreachable — the tool reports that check as unknown rather than guessing at a pass or fail.

Is checking someone's email domain like this ethical?

Checking whether a domain has MX records is equivalent to what any mail server does before attempting delivery — it's public DNS information, not private data about the individual.

Can I test many addresses this way at once?

This tool is built for testing one address at a time with full detail. For checking many addresses quickly on format alone, use the Bulk Email List Checker instead.

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