How do I verify a list of emails in bulk?

Bulk verification handles lists from a few hundred subscribers up to a million addresses per upload. The flow is: upload a file or paste your addresses, we process the list in the background, you download the cleaned results when the task finishes.

The step-by-step

1. Log into your dashboard and click Bulk Upload in the sidebar.
2. Drag your file onto the upload area, click to browse, or paste addresses into the text field directly.
3. Confirm the list name and review the email count.
4. Choose whether to remove duplicates before verification (on by default, recommended). If 500 of your 10,000 addresses are duplicates, we charge for 9,500 and verify 9,500.
5. Start the task. Cost is one credit per unique address.
6. Once it starts, you can close the tab. We'll email you when the task finishes, usually within a few minutes for lists under 10K.
7. Download the results from the Uploads & Results page when the task is complete.

What you get back

Each address in your file is returned with:

• The canonical status (Safe, Invalid, Disposable, Catch-All, Role Account, Spam Trap, Disabled, Inbox Full, or Unknown)
• A confidence score from 0 to 100
• Detailed flags (Free Email, MX Found, Deliverable, etc.) so you can filter granularly
• Any extra columns from your original CSV (names, signup dates, sources) preserved alongside the new verification columns

What happens to unknowns and duplicates

Duplicates are removed before we charge (when the option is on). Unknowns get re-tried through our secondary verification engine automatically. If both engines come back inconclusive on the same address, the credit is refunded — that address shows as Unknown in the export but does not count against your balance.