Core Tool — HarbiLeads App
An email verifier checks whether an email address is real and able to receive mail — without sending it a message. The HarbiLeads Email Verifier runs your addresses through format, domain and mailbox-level checks and labels each one valid, risky or invalid, so dead addresses never reach your campaign. When you send outreach from your own Gmail accounts, this is the step that protects them.
The Checks
The address is checked against the rules of a valid email format — typos like "gmial.com" or missing @ signs are caught immediately.
The domain must exist and publish mail (MX) records. A dead or parked domain means every address on it is undeliverable.
The mail server is asked — politely, without sending mail — whether this specific mailbox exists and accepts messages.
Some domains accept mail for any address, real or not. Those results are marked risky instead of valid, so you can decide with open eyes.
Role inboxes and throwaway addresses are flagged, helping you prioritise the contacts most likely to be read by a person.
Every address ends as valid, risky or invalid — a simple traffic light your whole campaign can be filtered on.
Why It Matters
HarbiLeads sends campaigns from your own Gmail or Google Workspace accounts, which is exactly why verification matters more here than in tools that send from their servers. Every bounced email is a small vote against your account. Stack up enough of them — a bounce rate above a couple of percent is enough — and Google starts treating your mail as suspicious: pitches land in spam, then accounts get restricted. The addresses are not the problem; the asset at risk is a sending account you may have warmed up for weeks.
Verification flips the order: check first, send second. Lists found with the Bulk Email Finder already carry a verification status, and any list you import — bought, scraped or collected by hand — can be verified the same way before the Email Sender touches it. The result is boring in the best possible way: low bounces, healthy accounts, and pitches that reach inboxes.
How It Works
Use emails found by the finder, or import any existing list of addresses into a prospect list.
HarbiLeads checks every address and marks it valid, risky or invalid directly in the grid.
Filter out the invalid rows, keep the valid ones, and launch your campaign knowing the list is clean.
FAQ
An email verifier is a tool that checks whether an email address is real and able to receive mail, without sending it a message. It validates the address format, confirms the domain and its mail servers exist, and probes whether the mailbox itself is live, then labels the address valid, risky or invalid.
Because bounces damage the Gmail account you send from. A list with many dead addresses produces a high bounce rate, which makes providers treat your mail as suspicious and pushes future pitches into spam. Verifying first keeps bounce rates low and your sending accounts healthy.
A catch-all (accept-all) domain is configured to receive mail for any address, even ones that do not exist as real mailboxes. Verification cannot fully confirm a specific mailbox on a catch-all domain, so those addresses are marked risky rather than valid — send to them carefully and in small numbers.
Valid means the mailbox exists and accepts mail — safe to send. Invalid means the address or domain is dead — never send. Risky covers catch-all domains, role accounts and other uncertain cases — send only if the prospect is worth it, and watch the replies.
Yes. Import any list of addresses into HarbiLeads and run verification on it before you send. Lists found with the Bulk Email Finder already carry a verification status, and re-verifying older lists keeps them clean as addresses go stale.
Credits are counted for finding emails — 1 credit per email found, refilled daily on the free plan. See the Pricing page for the full, current breakdown of how credits work across the app.
Use an email verifier. It validates the address format, confirms the domain and its mail servers, and checks with the mail server whether the mailbox exists — all without delivering a message. In HarbiLeads this check is built in: import or find your addresses and each one is labelled valid, risky or invalid before you send.
Download HarbiLeads free and verify your next outreach list before a single email is sent — your Gmail accounts will thank you.
Download for Windows See Pricing