CSV to Excel
Convert a CSV file to Excel (.xlsx) in your browser. Download a real spreadsheet — nothing is uploaded.
Merge CSV files
Combine multiple CSV files into one in your browser. Rows are stacked and headers aligned by name.
Drop CSV files here or click to choose
Combine locally — nothing is uploaded
How to use Merge CSV files
Merge multiple CSV files by stacking rows. Headers are aligned by name when possible.
Everything runs locally in your browser — your files are never uploaded to a server.
Merge CSV files FAQs
How do I merge CSV files online?
Add two or more CSV files, then download one combined file. Rows are stacked and headers are aligned by column name when possible.
Is merging CSV files free?
Yes. Every Excel and CSV tool on ReallyUseful.Tools is free to use, with no account or subscription required.
Are my files uploaded?
No. Files are processed in your browser on this device. Nothing is uploaded to our servers.
What if the CSV files have different columns?
Columns are unioned by header name. Missing values in a file are left blank in the merged output.
More Excel/CSV
Excel to CSV
Convert Excel .xlsx or .xls to CSV in your browser. Choose a sheet and delimiter, then download.
CSV viewer
Open and browse a CSV in a paginated table in your browser. No upload — view large files locally.
CSV to XML
Convert CSV rows into structured XML in your browser. Each row becomes an element — nothing is uploaded.
CSV to SQL
Generate SQL INSERT statements from a CSV file in your browser. Set a table name and download .sql.