CSV to Parquet
Turn CSV exports into columnar Parquet without shipping them to a random web converter. DataEngUtils compresses and types columns locally using Polars, which is what you want before loading a warehouse or sharing a smaller artifact with another team. The workflow is built for recurring pipeline tasks: drop a multi-hundred-megabyte export, infer or override dtypes, and write Parquet that downstream systems actually accept. Because everything runs on your Mac, you can convert customer files, finance extracts, and ad-hoc dumps that would never pass a security review if uploaded elsewhere.
Try it free
Available in the desktop app
CSV to Parquet processes local files with Polars in Rust. Multi-gigabyte Parquet and CSV workflows require the native macOS app — nothing is uploaded to the cloud.
SELECT
order_id,
customer_id,
created_at
FROM analytics.fct_orders
WHERE created_at >='2026-01-01'
How it works
1. Add CSV files
Drag one or more CSV files into the converter. Paths stay on local disk only.
2. Set schema hints
Review inferred types, fix columns that should be numeric or timestamp, and choose compression.
3. Write Parquet
Save .parquet output beside your source files or into a staging folder for ingestion.
Why not use an online tool?
Online converters tools require uploading your Parquet and CSV files to a third-party server. For production work, that is a security and compliance risk. DataEngUtils runs locally — same convenience, none of the exposure.