The tool removes duplicate rows from an Excel or CSV spreadsheet. The output is a cleaned file where only the very first occurrence is kept for each set of values or unique key. The service also provides a brief summary of exactly how many duplicates were found and removed.
When this is useful
The sales department maintains a general contact list in CSV, which over time has accumulated identical entries from different sources, and now needs to be cleaned before a mailing. Another example: an inventory system exported a warehouse statement with doubled positions by SKU, and only unique items need to be kept.
Step-by-step instructions
- Upload the source spreadsheet in XLSX, XLS, or CSV format.
- Select the deduplication mode: by the entire row or by one specific column, which you specify from the dropdown list.
- Click the processing button and, after completion, download the cleaned file.
How to verify the result
Compare the number of rows in the source and resulting files to ensure the difference matches the number of removed duplicates from the summary. Open the cleaned table and visually check a few records that you know were duplicated. Make sure that in column-based processing mode, necessary rows with empty values in the key field were not removed.
Important limitations
Always create a backup copy of the original, as the removal operation irreversibly changes the number of rows in the file. Rows consisting entirely of empty cells are also considered duplicates and will be removed if they occur more than once. Letter case and invisible spaces in cells affect the match determination.