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Never Send to a Bad Email Again

Clu checks each address three ways (the format, a live mail server, then the mailbox itself) and marks it Verified, Likely valid, Risky, Invalid or Unknown. Send to the first two and decide on the rest.

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Clu validating q4-webinar-signups.csv. Each address is marked Verified, Likely valid, Risky, Invalid or Unknown. Of 10,000 rows, 8,612 Verified, 604 Likely valid, 431 Risky, 287 Invalid, 66 Unknown.

10,000+ users, from founders to full sales teams

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The status tells you whether to send.

Verified and Likely valid go out. Risky addresses sit on catch-all domains that accept everything, so you hold them or test them at low volume. Invalid ones come off the list, and Unknown gets checked again later.

  • Verified8,612Send. The mailbox exists and takes mail.
  • Likely valid604Send at your normal pace.
  • Risky431Hold or test. The domain accepts anything.
  • Invalid287Remove. It would bounce.
  • Unknown66Check again later. The server didn't answer.

When an address fails, the waterfall looks for the new one.

An invalid address usually means the person moved on or the mailbox was shut down. Clu asks 25+ providers for their current work email, at 1 credit for a verified one.

The Clu waterfall looking for a work email. For Ben Trask it tries providers in order and stops at attempt 3, the first deliverable result, which costs 1 credit. For Sofia Marchetti all 7 attempts miss, and the charge is 0 credits.

Checking 10,000 signups cost 5,214 credits, half a credit an address.

You pay 0.5 credits to validate each address you already have, whatever status comes back. A verified replacement is 1 credit.

q4-webinar-signups.csv10,000 rows
  • ValidationEvery address in the file10,000 × 0.55,000
  • Replacement emailsFor the invalid ones214 × 1214
Total5,214

Check the list before the next send.

Upload the CSV you're about to send, or connect your CRM.

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