Check whether an email address can receive mail

See the privacy policy for how Emvero processes and retains the data used in a check.

What an email verification checks

A correctly formatted address is only the starting point. Emvero checks whether the domain exists and has a mail route before attempting a mailbox check. Later stages stop if an earlier one establishes a definite failure.

1. 01

   Syntax

   Check the address format, including the part before @, the domain and length limits. This stage needs no network connection.

2. 02

   Domain

   Look up the domain in DNS, the system that publishes domain records. A non-existent domain ends the check; a temporary lookup failure leaves the result uncertain.

3. 03

   Mail routing

   Find the domain’s mail route. MX records name its mail servers. A domain may use a fallback route or publish a null MX record to declare that it accepts no mail.

4. 04

   Mailbox probe

   At full depth, ask the receiving server about the mailbox when possible. The SMTP conversation stops before DATA, so no email is sent.

5. 05

   Classification

   Combine the findings into a status and recommended action. Reason codes explain the evidence, including any limits that leave the address uncertain.

If you only need to inspect the domain’s mail setup, use the free email domain checker. A working website does not mean the domain receives email, and a mail route does not establish that a particular mailbox exists.

How the mailbox check works without sending email

SMTP is the protocol mail servers use to receive email. When a destination permits a mailbox check, Emvero connects to its server and names the recipient. This simplified example shows a server accepting the recipient:

CONNECT    mx.company.com:25
EHLO       <our hostname>
MAIL FROM  <our return path>
RCPT TO    <name@company.com>
250 2.1.5 Recipient OK
RSET
QUIT

The conversation stops before DATA, the stage where a message would be submitted. No subject or body is sent.

Acceptance is evidence about this exchange. The server may apply different rules when a real message arrives, so the reply does not guarantee delivery. A refusal can also reflect restrictions on the probe rather than a missing mailbox. Emvero does not automatically reject an address based on an SMTP refusal.

What the result means

A completed check has one of four statuses. Read its recommended action as well: an address marked risky may be allowed or require email confirmation, depending on the reason.

A full check may first return pending while the mailbox check continues. Wait for the completed result before treating it as a final status.

The result also includes checks, which records the individual findings, and reason_codes, which explain them. Invalid syntax, a non-existent domain or a null MX record can establish undeliverable. A null MX record is the domain’s explicit declaration that it accepts no mail. A timeout or ambiguous SMTP refusal leaves the result unknown.

The action field recommends allow, allow_with_email_confirmation or reject. Use it together with the status and reasons. The guide to interpreting a verification result explains how to apply these fields in your workflow.

When an address needs closer review

A catch-all domain can produce a risky result because the individual mailbox remains uncertain. Other signals need different handling:

• A disposable-mail provider may offer a working mailbox that is temporary. An accepted recipient at such a provider can be risky with an allow recommendation. The free disposable email checker identifies the provider; it does not test the mailbox.
• A role account such as support@ belongs to a function or team. That attribute alone does not make it risky; it can still be deliverable.
• A suggested domain correction flags a possible typo. Let the person confirm a correction rather than changing the address automatically.

Decide how these signals affect your own use of the address. If access depends on someone controlling the mailbox, send your own confirmation email and require them to act on it. Emvero’s check does not establish control or send that confirmation for you.

Choose a full check or a domain check

Both depths use the same account balance. Choose the depth per check, according to the evidence you need.

Full check	Domain check
At most 10 credits	2 credits
Checks syntax, domain and mail routing, and may gather SMTP recipient evidence	Stops after syntax, DNS and mail routing; no SMTP session
Can establish new catch-all evidence where probing is allowed	Can report only an already-known catch-all state
May first return pending	Cannot establish an individual mailbox

A full check may cost less if it stops early. It can also finish as risky or unknown: “full” describes the scope of the check, not a guarantee of a conclusive answer. Neither depth guarantees future delivery or inbox placement.

Check addresses in your own workflow

Use the account checker for individual addresses. For checks within your application or across a list, use the same verification service through the API.