How to detect duplicate invoice numbers in an accounting csv
- Step 1Export the invoices or AR CSV — Download from Xero, QuickBooks, or your billing system.
- Step 2Drop into CSV Duplicate Finder — Select Invoice Number as the key column.
- Step 3Review the duplicate flag column — Every invoice number that appears more than once is marked.
- Step 4Resolve duplicates in your accounting system — Void or merge duplicate invoices before the next billing cycle.
Frequently asked questions
Can I see which rows are the original and which are duplicates?+
The flag column marks all instances of a duplicate group. The first occurrence is also flagged so you can compare all versions.
Does this work for purchase invoice numbers too?+
Yes. Any invoice number column in any CSV works.
Is there a row limit for the audit?+
Free handles up to 2,000 rows. Pro removes the limit for large AP/AR exports.
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