How to find duplicate leads in a csv before sales outreach
- Step 1Export or receive the lead CSV — Download from your lead gen tool, list provider, or form.
- Step 2Drop into CSV Duplicate Finder — Select the Email Address or Phone column.
- Step 3Review flagged duplicates — Duplicate rows are marked. Compare fields to choose the best version.
- Step 4Clean and import — Remove the unwanted duplicate rows and import the clean list.
Frequently asked questions
Should I check email and phone as separate passes?+
Yes. Run email as the key first, then run phone as the key to catch leads that have different emails but the same phone number.
Does this work across multiple lists merged into one CSV?+
Yes. Merge your lists with the CSV Merger first, then run the duplicate finder on the combined file.
Is contact data uploaded?+
No. All processing is in your browser.
Privacy first
Processing runs locally in your browser with PapaParse. No file is uploaded — only metadata counters are saved for signed-in dashboard stats.