Email list deduplicator

Deduplicating on the raw string leaves the duplicates that matter: the same person who signed up twice with a dot moved or a tag added. This normalises first, then compares.

Try:

Free, no signup, no daily limit. We do not store what you check here.

Why exact matching under-counts

Every deduplication that compares raw strings reports a number lower than the truth, and the addresses it misses are exactly the ones a person created on purpose to look different. Sending to all three costs three times the volume, produces one reader, and teaches the receiving provider that your list is not well maintained — which is the signal that moves you toward the spam folder for everybody.

Where this stops

It finds addresses that provably reach the same mailbox. It cannot find one person with two genuinely different addresses, which no tool can do from the addresses alone. And it makes no claim about whether any of them work: a perfectly deduplicated list of dead addresses is still a list of dead addresses.

Questions

Is my list sent anywhere?

It is processed to produce this answer and not stored. Nothing here needs a network lookup — normalisation is arithmetic on the string.

How many addresses can I paste?

Up to a thousand here. For more than that, the bulk endpoint quotes the job before it starts and charges nothing until you accept.

Related tools

When you need more than a free tool

This page answers what can be determined offline and from public DNS. The API adds live carrier and mailbox verification, a calibrated confidence score, and the full evidence trail behind every verdict.

Credits never expire. Inconclusive verdicts are never billed. Cancel in one call. See pricing or read the docs.