FREE WEB TOOL
Find identical rows or duplicate keys in selected CSV columns.
Files are processed in your browser and are not sent to our server.
Need to know whether an email address, SKU, or customer ID appears more than once? Pick one column and the tool lists repeated values with the CSV row numbers where they occur.
Two people can share a surname; two records may legitimately share a company or household email. The tool finds repeated keys. It does not decide that one row should be removed.
The check uses one selected column at a time. If your real uniqueness rule is a combination such as store_id + sku, create a composite key column first and test that column. The definition of “duplicate” changes with the key you choose.
ABC and ABC match because the selected cell is trimmed before comparison. Case is preserved, so ABC and abc are different values.
Only the edges are trimmed. Internal whitespace, full-width versus half-width characters, punctuation, and hyphen differences are not normalized. If your duplicate rule says those should match, normalize them before running the check.
A hundred blanks do not show up as one giant duplicate group. If you need to audit missingness, use a missing-value tool instead of a duplicate-key check.
Quoted cells may contain line breaks. The CSV parser treats that as one record, so the reported row number can differ from the physical line number shown by a plain text editor.
If SKU A-100 appears on rows 12 and 87, compare those two source records. One may be an obsolete item, a variant, or a true duplicate. The tool gets you to the suspicious rows; the business meaning decides the action.
The same applies to case rules: [email protected] and [email protected] remain different here. Decide what “same” means for the business field before treating the output as a final duplicate list.