Leadash Verifier
Bounces quietly wreck your sender reputation. Verifier catches the bad addresses before you hit send.
Upload a list of up to 50,000 or check a single address. Every email comes back with a clear verdict, and Leadash sequences only write to the safe ones. Your inboxes stay healthy, and your next pitch reaches the person you wrote it for instead of a spam folder.
How it works
Why verify
When too many of your emails bounce, mailbox providers start treating everything you send as suspect, and your best pitches end up in spam. Checking the list first is how you keep landing in the inbox.
Fewer bounces means providers keep trusting your domain, so the emails you worked hard on get read.
Mailbox-level checks: Verifier asks the receiving server whether that exact mailbox exists, not just whether the domain looks right.
Some servers say yes to every address. You decide whether a campaign takes that risk instead of finding out from bounces.
Catch-all domains are probed and flagged, so a server that accepts everything doesn't pass as Safe.
Business email lives on a handful of big providers. Verifier handles them on their own terms.
A dedicated check for Microsoft-hosted addresses; Yahoo-family addresses, which can't be probed directly, go through a specialist provider.
Your best message deserves a real decision-maker, not a throwaway inbox or a shared mailbox nobody reads.
Throwaway inbox services are marked Disposable; shared addresses like info@ or sales@ are marked Risky.
Start a job, get on with your day, and come back to a list you can send to with confidence.
Bulk jobs of up to 50,000 emails run in the background; verify lists in your leads pool and download results by verdict.
Keep every source of leads clean, whether they come from a form, a scraper or your CRM.
REST API with a completion webhook, plus Claude and ChatGPT, which ask for your approval before spending credits.
Verdicts
No vague scores to interpret. Each verdict says what we found and what your campaigns will do with the address, so you never have to decide on a hunch.
The facts
verification.completed webhook, and MCP tools for Claude and ChatGPT. See the developer docs.Pricing
Verification runs on the same credits as the rest of Leadash, and in bulk you only pay for real answers.
per email verified. In bulk jobs, any result we can't determine is refunded.
Email addresses go stale: people change jobs, companies change domains, and mailboxes get shut down. A list that was clean when it was built can still bounce today, and every bounce counts against the inbox that sent it.
A catch-all domain accepts mail for any address, so nobody can confirm a specific mailbox exists. Leadash holds catch-all addresses by default because they bounce more often. If you know the domain, you can let a campaign include them.
Not in bulk jobs or through the API. Unknown means the receiving server didn't give a clear answer, for example it timed out or temporarily refused the check, so a bulk job refunds those credits when it finishes and an API check isn't charged.
Up to 50,000 emails per CSV upload. Jobs run in the background; you can leave the page and download the results later.
Leadash sequences only send to addresses verified as Safe or Valid (or ones you mark as verified yourself), so unverified leads wait until they are checked. This protects your inboxes from bounces.
Yes. Upload any CSV of addresses or verify a single one. The tool is not limited to leads found in Leadash.
Yes. Verify single addresses or lists from your own code with the Leadash API and get a webhook when a job finishes. Claude and ChatGPT can run verifications too, each one confirmed by you.
Create a Leadash account, upload a list, and see exactly which addresses are safe to email before a single one bounces. Unknown results in bulk jobs are refunded.