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Duplicate Finder

Find and analyze duplicate rows in CSV or JSON datasets. Select columns to compare, review grouped duplicates, and export clean results.

Input Data

Options

Load data to see available columns
Finds duplicates as you type.

How It Works

Features
  • CSV & JSON support: Paste CSV text, JSON arrays, or upload files in either format
  • Column selection: Choose which columns to compare for duplicate detection
  • Flexible matching: Exact, case-insensitive, or trimmed comparison modes
  • Grouped results: Duplicates are shown in groups so you can see which rows match
  • Export options: Download just the duplicates or the deduplicated dataset
Common Use Cases
Data Cleaning
  • Find duplicate entries in mailing lists
  • Identify repeated records after data imports
  • Clean customer databases
Quality Assurance
  • Validate uniqueness constraints before database import
  • Audit spreadsheet data for accidental duplicates
  • Compare partial column matches (e.g., same email, different name)

Embed This Util

You can embed this util on your own site as a widget. Adding ?embed=1 to the URL loads a compact version with just the tool itself; no header, menu, or documentation. Paste this snippet into your HTML: 


    

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