Barcode Duplicate Finder
Paste values or upload a file and we list the duplicate barcodes and the rows they appear in.
How to use in 3 steps
- 1
Enter data
Paste barcode values one per line or upload Excel/CSV.
- 2
Choose the compare setting
Set matching rules like case and whitespace sensitivity.
- 3
Review the report
See which values repeat, how many times and on which rows, then download it.
Example input / output
Input
8690000000017 (rows 2, 5, 9)
Output
1 duplicate group · 3 times · rows 2,5,9
Technical notes
The tool normalizes each value in your list, compares them against each other, and groups barcodes that appear more than once. For each repeat it reports the row numbers where it occurs, so you can find the source fast.
Matching rules matter: leading/trailing spaces, invisible characters or different letter case can make two actually-identical values look different. For the most accurate result, normalize your data first with the barcode normalizer before comparing.
Duplicate barcodes cause serious confusion in inventory, POS and shipping systems: if one code points to two products, sales and stock data become unreliable. This tool lets you catch clashes before loading the file into a system.
All processing runs in your browser; your data is never sent to a server. To run a similar check during bulk generation, use the duplicate detection in the bulk barcode generator.
Frequently asked questions
If you normalize the data with the [barcode normalizer](/en/barcode-cleaner) before comparing, you can catch 'hidden' duplicates that are actually identical.