Convert CSV to Parquet

Select your CSV and get it in Parquet format in a few clicks. No server-side processing, everything happens in your browser.

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Quick Start

  1. 1
    Upload your CSV file

    Drag-and-drop a CSV file or click to browse. Everything stays in your browser.

  2. 2
    Select a delimiter

    Choose the delimiter used in your CSV — comma, tab, semicolon, or pipe.

  3. 3
    Convert to Parquet

    Click convert and your CSV is transformed to Parquet format using WebAssembly.

  4. 4
    Download the Parquet file

    Download the resulting Parquet file directly from your browser.

Specs

Input
.csv
Output
.parquet
Delimiters
, \t ; |
Engine
DuckDB WASM

Data stays on your device

All processing runs locally in your browser. Nothing is sent to any server.

Our CSV to Parquet converter uses WebAssembly to convert your CSV files directly in the browser. This ensures that your data never leaves your device, guaranteeing privacy and security. Parquet is a columnar storage file format optimized for analytics — highly efficient in both storage and performance while supporting all modern data processing tools.

0 bytes

Data transmitted

4

Delimiters supported

Automatic

Compression

100% Free

Our online CSV to Parquet converter is completely free to use, with no hidden costs or subscriptions.

Privacy-Focused

Your data never leaves your device. All processing happens locally in your browser using WebAssembly.

Fast and Efficient

Quickly convert even large CSV files to optimized Parquet format with our WebAssembly engine.

No Installation Required

Use our converter directly in your web browser, no software installation needed.

Is this CSV to Parquet converter private?

Yes. The converter runs entirely in your browser using WebAssembly. Your data never leaves your device.

What delimiters are supported?

We support comma, tab, semicolon, and pipe delimiters. Select the appropriate one before converting.

What is the advantage of Parquet over CSV?

Parquet is a columnar storage format optimized for analytics. It offers better compression, faster query performance, and supports complex nested data structures.

Can I use this tool offline?

Yes. Once the page finishes loading, you can disconnect from the internet and continue converting files offline.

Advantages of Parquet Format

Parquet is a columnar storage file format optimized for analytics. It's highly efficient in both storage and performance while supporting all modern data processing tools. Here are some key benefits:

How it works

Our tool uses WebAssembly to convert your CSV to Parquet directly in the browser. This ensures that your data never leaves your device, guaranteeing privacy and security. The process is as follows:

Parquet Structure

Understanding the structure of Parquet files can help appreciate its efficiency. A Parquet file is organized into rows and columns, but the data is stored in columns, allowing for the following structure:

  • Column Chunks: Each column is divided into chunks, which are then stored in separate pages. This structure facilitates efficient data compression and encoding.
  • Page Types: There are three types of pages - data pages, dictionary pages, and index pages, each serving a specific purpose in data storage and retrieval.
  • Row Groups: A set of column chunks that roughly correspond to a block of rows, allowing for more efficient reads of specific rows.
  • Metadata: Contains information about the file's schema, version, and other attributes necessary for processing the file.