ListCheckup
Clean your email list before you send. Every address comes back as valid, invalid, catch-all or risky, with the reason why. Credits are bought once and never expire, there is no subscription, and catch-all results are never charged for.
ListCheckup checks whether the addresses on a mailing list can actually receive email, before you send to them.
What you get back
Upload a CSV or call the API, and every address comes back as Valid, Invalid, Catch-all, Risky or Unknown, each with a confidence score and a plain-English reason. Results export to CSV, and every finished list gets a PDF report you can hand to a client.
Catch-all and Unknown are never charged for
A catch-all domain accepts mail for any address, so nobody can honestly confirm whether one particular mailbox exists there. We do not charge for those results, or for Unknown. Charging for a guess is how verification services inflate their accuracy claims.
Credits, not a subscription
Credits are bought once and never expire. Nothing resets at the end of the month and there is no plan to cancel. Packs run from EUR 5 for 1,000 verifications to EUR 149 for 100,000. The first 100 verifications every month are free and need no card.
Built in the EU
Checks run from servers in the EU. Uploaded lists are deleted on a retention window you choose, 90 days by default. The interface and the notification emails are available in English, German, Spanish, French and Italian.
For developers
A REST API with webhooks for job completion, and an MCP server so an AI assistant can verify addresses directly.
- Freemium
- €5 / One-off (1,000 verifications, credits never expire)
- Official Pricing
- Web
- REST API
