Features
Every check we run on an email address
MailVerify runs eight independent checks on each address, from syntax to a live SMTP mailbox lookup, then rolls them into one deliverability score. Built for agencies that need clean lists before every send.
The verification checks
Each check runs in order and short-circuits as soon as an address is proven undeliverable, so verification stays fast even at list scale.
Syntax & format validation
Every address is checked against the email specification and normalized first. Typos, illegal characters and malformed domains are caught before any network check runs, so you never waste a lookup on an address that was never valid.
MX & domain records
We resolve the domain and confirm it has live MX records, meaning real mail servers that can accept email. Domains with no MX cannot receive mail, so those addresses are flagged as undeliverable immediately.
SMTP mailbox check
We open an SMTP conversation with the receiving server and ask whether the exact mailbox exists, then disconnect without delivering anything. This is the difference between guessing a domain is fine and confirming a specific inbox is real.
Catch-all detection
Some domains accept mail for every address, which makes a single mailbox impossible to confirm. We detect catch-all configurations and mark those results as risky so you can decide how to treat them instead of trusting a false positive.
Disposable address detection
Throwaway and temporary mailbox providers churn constantly and bounce soon after signup. We flag disposable domains so they never make it into a client campaign.
Role address detection
Addresses like info@, support@, sales@ and admin@ route to shared inboxes and hurt deliverability in cold outreach. We label role accounts so you can exclude or down-prioritize them.
Free-provider detection
We identify free consumer providers such as Gmail, Outlook and Yahoo. That context helps agencies segment business prospects from personal addresses when building B2B lists.
Deliverability score
Every signal above rolls up into a single deliverability score per address, so a non-technical teammate can clean a list at a glance without reading raw SMTP responses.
Bulk CSV verification
Clean an entire list in one pass
Upload a CSV of any size, run every check on every row, and export the results tagged valid, risky, invalid or unknown. Keep the deliverable addresses and drop the rest before the list ever reaches your sending tool. Bulk export is included on the Pro and API plans.
Verification API
Wire verification into your pipeline
The API plan exposes REST endpoints and API keys so you can verify addresses the moment they enter your enrichment flow, CRM or outreach automation. Webhooks deliver results back asynchronously, so large jobs never block your workflow.
Feature FAQ
Do you send a real email to verify the address?+
No. We open an SMTP conversation with the mail server and ask whether the mailbox exists, then disconnect. No message is delivered, so the recipient never sees anything.
Can I verify a whole list with the bulk feature?+
Yes. Upload a CSV, verify the full list, and export the results tagged by status. Bulk CSV export is available on the Pro and API plans.
What is the difference between MX and SMTP checks?+
The MX check confirms the domain has mail servers that can receive email. The SMTP check goes further and confirms the specific mailbox on that server exists. A domain can pass MX while the individual mailbox does not exist.
Is there an API?+
Yes. The API plan gives you REST endpoints and API keys to verify addresses inside your own enrichment pipeline, CRM or outreach automation, with webhooks for results.
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