How to Convert CSV to Parquet Online (Free, No Upload)

Convert CSV to Parquet in seconds, right in your browser, with no install and no account.

Large CSV files are slow to open and heavy to store. Tools such as Spark, DuckDB, BigQuery and pandas read Parquet much faster, because it stores data by column and compresses it.

The converter reads your CSV, detects the type of each column and writes a compact Parquet file. The file is often several times smaller than the CSV, and each column keeps its real type.

Your file is processed in your browser and is not uploaded to a server, so it is safe to use with customer or business data.

Open the CSV to Parquet converter

How to use the CSV to Parquet converter: step by step

1. Open the CSV to Parquet converter.
2. Drop your file into the box, or paste the data.
3. Click Convert.
4. Copy the result, or click Download to save the Parquet file.

When to use the CSV to Parquet converter

• Preparing data for Spark, DuckDB or BigQuery
• Shrinking a large CSV before you store or share it
• Speeding up analysis in pandas or Polars
• Keeping column types such as dates and numbers

Tip: Parquet is a binary format, so you cannot read it in a text editor. Use the Parquet to CSV converter to check the result.