Combine Columns in Parquet Files Online
Combine multiple columns into one in Parquet 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.
Drop your .parquet file here
or click to browse — max 50 MB
About this tool
Combine two or more columns in a Parquet 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 Parquet 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 Parquet 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 Parquet 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.
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