When to use CSV / JSON to Parquet?
Turn CSV, TSV, JSON or NDJSON into typed compressed analytical Parquet directly in the browser.
- Prepare a file for a data lake
- Shrink a large analytical CSV
- Select and reorder columns while checking text codes
Spreadsheets & data · ONLINE TOOL
CSV / JSON to Parquet
Select, reorder and rename columns, preserve CSV text codes and review the compressed Parquet before export.
Local processingNo account required
CONCRETE EXAMPLE
CSV → Parquet
BEFORE
→sales.csv
AFTER
sales.parquet · Snappy/Zstandard compression
Your data stays in the browser
Processed content is not uploaded to WorkToolset. Required libraries may be loaded by the site, but the file stays in the browser.
Limitations to know
- Types are inferred by default; CSV/TSV all-text mode preserves codes with leading zeros.
- Files above 100,000 rows are blocked rather than silently truncated.
A straightforward workflow.
- 1Prepare the required input and choose useful options.
- 2Review previews, warnings and limitations before export.
- 3Download a new copy or report: the original stays unchanged.
Frequently asked questions
Are my files uploaded to WorkToolset?
No. This tool runs locally in your browser.
Is my original file modified?
No. WorkToolset creates a new copy or export.
Do I need an account?
No for this free tool. Accounts are mainly used for favorites, presets and future workflows.