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Remove Duplicates in Excel — Online Excel/CSV Deduplication, Column Rules, Local Processing
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Fast, privacy-first deduplication for Excel (.xlsx) and CSV. Select columns as unique keys, configure keep-first/keep-last strategy, and normalize text (trim, lower-case, punctuation, full-width→half-width) before removing duplicates. Runs fully in your browser with preview, progress, and one-click download to Excel/CSV.

Features

Excel/CSV Support
Multi-Column Keys
Keep First/Last
Text Normalization
Local Processing
Preview & Progress
One-click Download
Internationalization
+1 more features

Excel Duplicate Remover
v1.0

Quickly remove duplicates in Excel and CSV files. Choose columns, configure rules, and normalize text — all processed locally in your browser.

Upload Excel or CSV File

Drag file here, or click to select

Supported: .xlsx, .csv

Max Size: 20 MB

Upload tips

  • Supports common .xlsx and .csv formats
  • Keep the file under the maximum limit for smoother processing
  • Keep column headers in the first row to help identify fields
  • We auto-detect format and parse it for you, no extra settings required

How to Use

Supported formats: Excel (.xlsx) and CSV (.csv)
Max file size: 20MB
Dedup principle: determine duplicates by selected column combination
Data privacy: processed locally in browser, not uploaded to server
Processing Steps
  1. Upload Excel or CSV file
  2. Choose columns for duplicate detection
  3. Configure processing options
  4. Run and download results

Usage Examples

Basic Usage

Remove Duplicates in Excel — Quick Start

Usage Steps:

  1. Upload — Select an Excel (.xlsx) or CSV file. The tool analyzes headers, sample values, and row count locally.
  2. Choose Columns — Tick one or more columns as the unique key for duplicate detection (e.g., Email + Phone).
  3. Set Options — Choose 'Keep First' or 'Keep Last'; enable normalization like Trim/Lower-case/Punctuation/Full→Half Width.
  4. Run — Start processing. View progress and summary: original rows, duplicates removed, unique rows retained.
  5. Download — Export the cleaned dataset to Excel or CSV with a single click.

Features:

  • Multi-Column Deduplication — Combine columns to define row uniqueness
  • Keep Strategy — Choose to keep the first or last occurrence of duplicates
  • Normalization — Trim whitespaces, convert to lower-case, normalize punctuation, full-width→half-width
  • Local-first — All processing stays in the browser; no server upload
  • Result Summary — See counts of original, duplicate, and unique rows
  • Export — Download to .xlsx or .csv instantly

Use Cases:

  • Email List Cleaning — Remove duplicate subscribers across merged lists
  • Sales CRM Merging — Deduplicate leads by Email + Phone or Company + Name
  • Event Registrations — Clean attendee sheets before badge printing
  • Product Catalog — Collapse duplicate SKUs while keeping latest updates
  • Academic Datasets — Ensure unique participants or records by ID
  • Finance Exports — Normalize payee names and remove duplicate transactions

Common Questions (Q&A):

  1. Q: How do I remove duplicates by multiple columns in Excel?
    A: Select all relevant columns as the unique key (e.g., Email + Phone). The tool treats rows with identical values across these columns as duplicates.
  2. Q: What is the difference between 'Keep First' and 'Keep Last'?
    A: 'Keep First' preserves the first encountered row among duplicates; 'Keep Last' keeps the most recent occurrence if your data is time-ordered.
  3. Q: Is my file uploaded to a server?
    A: No. All parsing, normalization, and deduplication happen locally in your browser for maximum privacy.
  4. Q: Will normalization change my data permanently?
    A: Normalization affects how duplicates are detected. The exported result reflects the cleaned values so your dataset stays consistent.
  5. Q: Which output format should I choose, Excel or CSV?
    A: Choose Excel (.xlsx) to preserve formatting and wide compatibility; choose CSV for lightweight interoperability and pipelines.
Remove Duplicates in Excel — Online Excel/CSV Deduplication, Column Rules, Local Processing - Master Tools