Free Email Verifier

Yes. Our free trial includes 1,000 verifications by CSV upload. Beyond this to integrate your CRM like Hubspot or Sales Engagement Platform like Outreach or Salesloft you can move onto one of our other plans.

Three ways. Connect Allegrow via one of our native integrations so records are verified without an export. Send a segment through bulk CSV upload. Or call the API from your own workflow. Native integrations are the usual choice for ongoing CRM data cleaning and automated outbound sequences, because contacts get re-checked as they change and every outbound email to a new prospect is automatically verified before the email is sent .

Yes, but only with advanced methods. Most tools label all emails on catch-all domains as “unknown”, “catch-all” or “accept-all / risky” whether they’re valid or not, since the servers of these contacts say all SMTP ping requests are correct, hiding which ones are real contacts. Allegrow uses proprietary techniques to verify these individual emails at the contact level, analyzing multiple signals to determine which are safe to send. This unlocks valuable contacts others discard, especially since catch-alls can make up to 40% of B2B lists. Allegrow helps you safely reach these leads while avoiding bounces, spam traps, and reputation damage.

No. Sending test emails to verify accounts is a dangerous practice that burns IPs and gives unreliable results, as many servers won't send a bounce back (NDR) even when an email is sent to an invalid inbox. A test email approach would falsely mark these as "Valid", filling your data-set with invalid contacts. We use proprietary signals to definitively confirm existence, providing higher reliability on results by eliminating the false positives associated with email-based testing.

An email verifier, also called an email checker, confirms whether an address exists and can receive mail. It checks the syntax, looks up the domain's MX records, then opens an SMTP connection to the mailbox itself. A good one returns a conclusive verdict. A weak one returns "Unknown" on the catch-all and corporate domains that matter most in B2B.

Because sending to an address that doesn't exist means your overall usage of the email channel is less successful. Mailbox providers treat bounces as evidence you don't know your audience, and that lowers the sender reputation deciding whether your next campaign reaches the inbox. Verification removes bounces, spam traps and dead mailboxes before they enter a sequence, flags contacts who have changed jobs, and identifies which of a person's addresses is their primary inbox.

The cost is rarely one bounce. Mailbox providers read bounce rates as evidence you do not know your audience, and spam trap hits can quickly cause a domain to get blacklisted. Because reputation attaches to the domain, the damage lands on everyone sending from it, not just the campaign that caused it. Undoing a spam suspension takes weeks, not days.