Find Duplicate Rows in a CSV
Instantly spot strictly identical rows in a CSV file, with their occurrence count and the position of their first occurrence.
How it works
Have you merged several exports and suspect duplicate rows, or want to verify a file's integrity before importing it into a database? The tool compares every row (all columns) against all others: strictly identical rows are grouped, with their total occurrence count and the data-row number where they first appear.
Is a partially identical row (only one column different) detected?
No, only rows that are strictly identical across all their columns are considered duplicates. If even a single cell differs, the rows are treated as distinct.
What does “first occurrence, data row #X” mean?
This number counts only the data rows, excluding the header: row #1 is therefore the first row after the CSV header.
100% local processing: detection runs entirely in your browser via WebAssembly — your CSV file never leaves your device.