Merge multiple CSV files into one. Drag to set merge order, validate column alignment, map mismatched columns, and download a single clean CSV. No uploads required.
Upload any number of CSV files, set the exact merge order, and resolve column differences before merging.
Your CSV files are processed entirely in your browser. We never see your data.
Click to browse or drag and drop multiple files at once
Upload 2 or more CSV files. Drag cards below to set merge order.
Next step
Need to clean or split this merged CSV?
Trim whitespace, reformat fields, remove duplicates, or split by row count.
Upload any number of files, set the order, validate columns, and download a single merged CSV. Everything runs in your browser.
Click the upload zone or drag and drop two or more CSV files. Each file is parsed in your browser. Nothing is sent to a server.
Drag the file cards to set the exact order. Rows from File 1 appear first in the merged output, then File 2, and so on.
The tool checks column alignment across all files. If columns match exactly, you can merge immediately. If not, choose Union mode or use the mapping panel to align columns.
Click Merge. Your files are combined and downloaded as a single UTF-8 encoded CSV file, ready to use in any platform, database, or spreadsheet tool.
Splitting data across multiple files is common in research, CRM exports, and survey platforms. Merging brings it back together for analysis or re-import.
Survey platforms often export wave-by-wave or by date range. Merge multiple response exports into a single dataset for unified analysis.
If you previously split a large CSV to meet platform import limits (like Qualtrics SDS 100K rows), merge the parts back into one file after processing.
Combine contact lists from different sources, regions, or time periods. Merge them in order, then use CSV Cleaner to remove duplicates.
Field researchers or call centre agents often work in separate files. Merge all agent files into a single master dataset in one step.
CRM exports often come in segments by account, region, or date. Merge all segments into a single file before cleaning or re-importing.
Multiple database queries producing separate CSV outputs can be merged here before loading into analysis tools, BI platforms, or data warehouses.
Common questions about merging CSV files online.
From the makers of this free tool
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