# CSV Deduplicate Rows Upload a CSV file or paste CSV text, remove duplicate rows using exact or fuzzy matching, and download a cleaned CSV. > Canonical page: https://test.elysiatools.com/en/tools/csv-deduplicate-rows - **Category:** Data Processing - **Keywords:** csv dedupe, deduplicate rows, csv clean, remove duplicates, data cleaning, spreadsheet cleanup ## Overview Useful for CRM exports, lead lists, survey data, and spreadsheet cleanup when you need row-level deduplication with a downloadable result. ## Inputs - **CSV File** (file): Upload a CSV file if you prefer not to paste data - **Paste CSV Data** (textarea): Paste CSV content here when working from copied data - **Deduplication Columns** (textarea): email, phone or name, email - **Deduplication Strategy** (select) - **Enable Fuzzy Matching** (checkbox) - **Fuzzy Match Threshold (0-100)** (range) - **Case Sensitive Matching** (checkbox) - **Trim Whitespace** (checkbox) - **Preserve Original Order** (checkbox) - **Output File Name** (text): cleaned-customers ## When to use - When preparing CRM contact lists or sales leads that contain redundant email addresses or phone numbers. - When merging multiple survey response sheets where respondents might have submitted duplicate entries with minor spelling variations. - When cleaning up raw database exports before importing them into a new system or analytical tool. ## How it works - Upload your CSV file or paste the raw CSV text directly into the input area. - Specify the target deduplication columns and choose your strategy, such as keeping the first, last, or most complete record. - Configure matching preferences like fuzzy matching thresholds, case sensitivity, and whitespace trimming. - Process the data and download your cleaned CSV file. ## Use cases - Removing duplicate email addresses from marketing newsletter subscription lists. - Consolidating customer records from multiple CRM exports by matching names and phone numbers. - Cleaning up survey data where users submitted multiple responses with slight typos in their names. ## Frequently asked questions ### Can I deduplicate based on specific columns? Yes, you can specify one or more column names to target for deduplication, such as email or phone. ### What is the 'most complete record' strategy? This strategy evaluates duplicate rows and retains the row containing the fewest empty or null values. ### How does fuzzy matching work? Fuzzy matching identifies duplicates with minor spelling differences or typos based on a similarity threshold you set from 0 to 100. ### Does the tool modify my original file? No, the tool processes your data locally or securely in-memory and outputs a new, cleaned CSV file for download. ### Can I preserve the original row order? Yes, checking the 'Preserve Original Order' option ensures the output rows remain in their original sequence. ## Related tools - [BOM Character Remover](https://test.elysiatools.com/en/tools/data-bom-remover): Remove BOM (Byte Order Mark) characters from text and file content. 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