DievioCSV Duplicate Remover
Remove duplicate rows from a CSV by matching an entire row or a column such as email or contact ID. Review removed rows and download a CSV with every original column.
How to use this tool
- Paste or load a CSV with a header row.
- Match the entire row or select a key column. Choose whether case and outer spaces matter.
- Review which rows were removed and download the cleaned CSV.
A worked example
Input
Contact ID,Work email,Job 001,jane@example.com,Founder 002,jane@example.com,Advisor
Output
Removed CSV row 3 matches kept row 2. Contact ID,Work email,Job 001,jane@example.com,Founder
Choose Work email to match the two records even though their IDs and titles differ. The first record keeps all of its fields.
What the result means
The report lists each removed record and the first matching record. CSV row numbers count the header and any blank records. A quoted multiline cell belongs to one record.
Requires named columns and supports up to 10,000 data rows and 2 MB. It keeps the first match and leaves populated rows with a blank selected key in the file.
Frequently asked questions
Can I remove duplicates by email and keep every column?
Yes. Select the email column as the key. The output keeps every source column from the first matching row. Use All columns if you want the entire row to match.
What happens to rows with a blank key?
If you select a key column, rows with an empty or whitespace-only key stay in the file. Fully empty records are skipped.
Does ignoring case or spaces rewrite my CSV values?
The option only changes how values are compared. The retained row keeps its original text. The CSV export escapes spreadsheet formula prefixes.
Is this free, and are my inputs uploaded?
Use this tool without an account, subscription or credits. Processing and file exports run in your browser; the tool does not upload your inputs or send emails. Clear inputs to remove the current data. Inputs are not saved when you reload the page.
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