Combine Columns in Excel Files Online
Combine multiple columns into one in Excel files directly in your browser. Merge first name and last name, join address fields, or concatenate any columns with a custom separator — no upload required.
About this tool
Combine two or more columns in a Excel file into a single new column with a custom separator. Merge first and last names, build full addresses, or join codes — without writing a formula or opening a spreadsheet.
Frequently Asked Questions
Can I concatenate more than two columns in a Excel file?
Yes. Add as many columns as you need and they are joined in the order you select them.
Can I add a separator between values when combining columns in a Excel file?
Yes. Choose any separator — space, hyphen, comma, pipe — or leave it blank to concatenate values directly with no separator between them.
What happens if a column value is null when concatenating columns in a Excel file?
Null values are treated as empty strings by default, so the separator still appears. Run the Fill Empty Values tool first if you want to replace nulls before concatenating.
Is my data private?
Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.
What is the maximum file size?
The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.
Related Tools
Find Arg Max / Min in Excel Files Online
Find the value of one column at the row where another column is maximum or minimum in Excel files — directly in your browser. Optionally group by a category to get per-group results. No upload required.
Excel Viewer Online
View and inspect Excel files directly in your browser. Browse rows, check column names and data types — no upload required, your data stays on your device.
Convert CSV to Excel Online
Convert CSV files to Excel format directly in your browser. No upload required — your data never leaves your device.
Convert Parquet to Excel Online
Convert Parquet files to Excel format directly in your browser. No upload required — your data never leaves your device.
Convert JSON to Excel Online
Convert JSON files to Excel format directly in your browser. No upload required — your data never leaves your device.