Free browser tool
Find exact repeats before they distort the totals.
Choose the columns that define a record, find exact repeats, and export flagged rows for review.
- Your file stays in this browser tab.
- No account or upload required.
- Only tool activity is measured—never your file contents.
Quick Duplicate Checker
Exact matching only · Results require human review before any deletion
Drop a CSV here or choose a file
Maximum 20 MB · First row must contain column headings
What makes a record the same?
Select one or more columns. All selected values must match.
No columns match your search.
—Data rows
—Rows in duplicate groups
—Duplicate groups
—Blank keys skipped
Review duplicate groups
Matching rows are grouped below.
Kithms analytics never receive your filename, column headings, cell values, row counts, duplicate keys, results, or exported file. Closing or refreshing this tab clears the working data from the page.
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