Data Converter

Convert a dataset between common data-science formats — everything happens in your browser, your file is never uploaded.

1. Upload your data

Drop a file or click Choose File. We auto-detect the format from the extension.

Supported input formats:

CSVTSVTXT JSONJSONL / NDJSON Excel (.xlsx, .xls) ParquetFeather / Arrow IPC

Maximum file size: 50 MB. Note: .rda (R) and .pkl (Python pickle) are not supported in-browser — export them to CSV or Parquet first.

Drag & drop your file here, or

Powered by PapaParse (MIT), SheetJS (Apache 2.0), hyparquet (MIT), and Apache Arrow JS (Apache 2.0).
Open-source acknowledgements

About the Data Converter

The Data Converter turns a dataset in one format into another — CSV in, Parquet out; Excel in, JSONL out; whatever pairing you need. Everything runs in your browser using PapaParse, SheetJS, hyparquet, and Apache Arrow JS, so the file never leaves your device. Drop in a file up to 50 MB, eyeball the inferred column types in the preview, then export to the format your next tool actually wants.

What you can convert between

Common uses

Tips

Everything happens locally. No upload, no cloud step, no waiting for a server — and no chance of a private dataset ending up somewhere it shouldn’t.

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