EXCEL TUTORIAL · FREE TOOLS
Contents
Find Duplicate CSV Rows Online
Free online tool · No signup · Runs in your browser
Find all rows belonging to duplicate groups, with source row numbers and occurrence counts.
Your data stays in this browser tool. No account or upload to a processing service required.
Instructions
- Paste data, select header and case comparison options, and click Find duplicates.
- Download the report if needed.
Understanding your result
The sample contains two Alice,Dublin rows. Both belong in the duplicate report, with their source positions, so you can decide which occurrence to keep. Two people sharing a name are not necessarily duplicates unless every compared field also matches.
What to do if you have a problem
If expected duplicates are missing, inspect spaces and the case comparison option. A trailing space or different city creates a different complete row. Check the header option so the first row is treated as a heading when appropriate.
What to know before using the result
Maximum 2 MB and 20,000 rows. Compares entire rows as text, including whitespace. All duplicate occurrences appear in the report. Source row numbers include a header.
These tools work with pasted text or supported CSV files rather than Excel workbook files. CSV exports contain values and do not preserve workbook formatting, formulas or multiple worksheets. Formula builders produce formula text to use in Excel. Data processing runs in the browser tool.
Try an example
Name,City Alice,Dublin Bob,Cork Alice,Dublin
Summary
Use the source row numbers to review repeated complete records before deciding which to keep.