UseCase Solution

Merge Excel Files and Remove Duplicates

Combine multiple Excel or CSV files, align matching headers, and remove duplicates across the merged data.

100% Local Processing

Large File Ready

Instant Results

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The Problem

You have customer lists from different sources - marketing, sales, events. Excel can only deduplicate within a single file. Manually combining files means copy-pasting, aligning columns, and missing duplicates across files.

Our Solution

Upload all your files at once. We automatically detect column headers, align data across different structures, and remove duplicates across the entire merged dataset. Keep the newest record, the one with the highest value, or merge data from duplicates.

Key Features

Features optimized for this use case

Multi-file upload

Auto column alignment

Cross-file deduplication

Smart merge strategies

Keep newest/oldest/max/min

Export merged results

Download a Merge Excel Sample

Try the workflow with two small customer-list files, then compare your export with the expected result.

Rule: match Email while ignoring case, then keep the newest UpdatedAt record.

Marketing leads

First input CSV

Second input CSV

Expected clean list

Result for comparison

How It Works

Complete data cleaning in three simple steps

Upload Files

Drag all your Excel/CSV files

Configure Rules

Select columns and strategy

Download Result

Get one clean, merged file

FAQ

Common questions about this use case

Yes! We automatically align columns by name. Missing columns are filled with empty values.

Upload multiple files. For many or large files, process them in batches.

Rename different headers to the same name before processing so the columns align correctly.

Ready to Clean Your Data?

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