♪ II · Verify

Email Verifier. Four verdicts, no fiction.

valid, invalid, catch_all or unknown. We sell the verdict, not the validity: when the signals don't allow one, unknown comes back free.

99.4% binary precision on Microsoft 365 · unknown = free

mozartemail.com / verifylive demo: click to take over

1 · Fill in → 2 · Run it

99.4% binary precision on Microsoft 365 · four honest verdicts

Start free with 50 verified credits

No credit card required · 50 free credits

The problem

Thirty categories is not an answer.

Elsewhere

Most verifiers return dozens of statuses, park a third of your list under 'risky', and bill every row regardless. After paying, you still don't know what you can send.

At Mozart

Mozart returns four verdicts and prices them honestly. valid, invalid and catch_all are answers you can act on, at 0.1 credit each. unknown means the server wouldn't say, and costs nothing.

The mechanism

How a verdict is earned.

1

Syntax and DNS

Malformed addresses and domains without MX records are settled before a single network call.

2

Microsoft 365

M365 domains get their own out-of-band channel: 99.4% binary precision.

3

SMTP dialogue

Everywhere else, a live SMTP conversation asks the server itself, without sending an email.

4

The verdict

valid, invalid or catch_all: 0.1 credit. The server stalls, greylists or blocks: unknown, 0 credits.

Side by side

Verifier against verifier.

ElsewhereAt Mozart
36 categories and a 'risky' pilefour verdicts you can act on
Catch-all skipped, or guessed as validcatch_all named for what it is
Tuned for newsletter hygienecalibrated for cold outreach and sender reputation
Every row billed, whatever came backno verdict = 0 credits
Measured, not promised

99.4%

binary precision on Microsoft 365

Measured through Microsoft's own out-of-band channel. When Mozart says valid on an M365 domain, it's valid.

Start free with 50 verified creditsHow it's proven →

No credit card required · 50 free credits

Single · bulk · API

One address, a list, or your own code.

Single

Paste any address in the widget above and read the verdict, live, three free runs a day.

Bulk

5 000 rows per file, ten verdicts per credit, unknown rows free. The job keeps running after you close the tab.

API

POST /api/verify names the signal behind each verdict in reason, so a hard bounce and an unreachable server never look alike in your logs.

POST /api/verify
{"email": "johann.bach@leipzig-cantata.com"}
200 OK
{
"ok": true, "billable": true, "charged": 0.1,
"result": "valid", "reason": "smtp_rcpt_exists",
"provider": "m365", "confidence": 99
}

Explore the API →

Where it fits

Before anything gets sent.

SDR teamsRe-verify the list your last provider sold you before it burns your sender domain.
AgenciesHand clients a deliverability report with verdicts you can defend, row by row.
RevOpsGate CRM imports on valid, quarantine invalid, pay nothing on unknown.

Compose with

Email finder → Email verifier → Reverse lookup

Verify what any source produced. Then put a name on whoever replies.

Questions, answered whole

What list owners ask.

Is an invalid verdict billed?−

Yes, 0.1 credit, the same as valid. The verdict is the product: knowing an address is dead before you send it is exactly what protects your domain. Only unknown, where no verdict exists, is free.

How do you verify Microsoft 365 addresses?+

Through Microsoft's own out-of-band channel rather than plain SMTP, which M365 deflects. Binary precision measured there is 99.4%.

What does catch_all mean?+

The domain accepts every address, so no individual mailbox can be proven by surface checks. Mozart names it instead of guessing. If you want an address on such a domain anyway, the Email finder runs deeper signals and returns one only when it's highly probable.

Why only four verdicts?+

Because four is what a decision needs: send, don't send, domain accepts everything, server wouldn't say. Thirty intermediate labels move the guessing from the vendor to you.

How much does a 5 000-row list cost?+

At most 500 credits, since a verdict is 0.1 credit. In practice it lands lower: every row the servers refuse to answer for comes back unknown and deducts nothing.

99.4% on M365.
unknown costs 0.

A verdict you can act on, or nothing on the bill.

Start free with 50 verified credits

No credit card required · 50 free credits