Contact Compare Two Lists
Questions, corrections, or suggestions: email [email protected]. That mailbox is the only contact channel. There is no account page and no upload form, because the tools never receive your lists.
If a match looks wrong
Send two short lines that should have matched or stayed apart, and say whether Ignore case and Trim spaces were on. A few rows are enough. Do not send a full customer list or other private data just to report a bug.
The about page explains the matching rules. The privacy policy explains what the site does not collect from the tool.