What it does
Upload a contact or mailing list CSV. Get back a deduplicated list — with a separate file of the removed duplicates so you can review what was dropped.
The problem it solves
Mailing lists accumulate duplicates from form submissions, CRM imports, and list merges. Exact-string matching misses "123 Main Street" vs "123 Main St" or "Bob Smith" vs "Robert Smith". This tool uses fuzzy matching so near-duplicates are caught too, not just exact ones.
What it handles automatically
- Exact duplicates — Same email address, same name and address
- Fuzzy address matching — "123 Main St" matches "123 Main Street"
- Name variants — Configurable: match on email only, on name + address, or on address alone
- Merge strategy — When a duplicate is found, keep the row with more complete data, or always keep the first/last occurrence
- Review file — Downloads a second CSV of removed rows so you can verify before discarding
FAQ
Can I control how aggressive the fuzzy matching is? Yes. You can set the match threshold from "exact only" to "loose" depending on how confident you need to be.
What fields does it match on? You choose: email, full name + address, or just address. More fields = higher precision, fewer false positives.
Does it store my data? No. All processing is in your browser. Contact data never leaves your machine.