9 Best Free Open-Source Tools to Convert Large CSV Files to JSON Efficiently

Converting CSV files is straightforward with many tools available. However, handling large data files can be challenging without reliable tools or scripts.

Here, we present the best open-source tools for converting large CSV files into JSON.

1- CSVTOJSON (NPM)

csvtojson module is a comprehensive nodejs csv parser to convert csv to json or column arrays.

It can be used as node.js library / command line tool / or in browser. 

Features

• Strictly follow CSV definition RFC4180
• Work with millions of lines of CSV data
• Provide comprehensive parsing parameters
• Provide out of box CSV parsing tool for Command Line
• Blazing fast -- Focus on performance
• Give flexibility to developer with 'pre-defined' helpers
• Allow async / streaming parsing
• Provide a csv parser for both Node.JS and browsers
• Easy to use API

GitHub - Keyang/node-csvtojson: Blazing fast and Comprehensive CSV Parser for Node.JS / Browser / Command Line.

Blazing fast and Comprehensive CSV Parser for Node.JS / Browser / Command Line. - GitHub - Keyang/node-csvtojson: Blazing fast and Comprehensive CSV Parser for Node.JS / Browser / Command Line.

GitHubKeyang

2- CSV2JSON (Java)

CSV2JSON is a Java app that enables you to convert CSV files, commonly used for tabular data, into JSON format. This conversion allows for better data management, analysis, and sharing among employees.

GitHub - urvishkapadiya/CSV-to-JSON-Converter: CSV2JSON enables you to convert CSV files, commonly used for tabular data, into JSON format. This conversion allows for better data management, analysis, and sharing among employees. Whether it’s rental records or car maintenance history, CSV2JSON handles the transformation seamlessly.

CSV2JSON enables you to convert CSV files, commonly used for tabular data, into JSON format. This conversion allows for better data management, analysis, and sharing among employees. Whether it&#39…

GitHuburvishkapadiya

3- csvkit (Python)

csvkit is a suite of command-line tools for converting to and working with CSV, the king of tabular file formats.

One of its cool features is allowing developers to easily transform CSV from and to several formats as TSV,Excel and JSON files.

csvkit 2.0.1 documentation

csvkit 2.0.1 documentation

4- csv2json (Python)

csv2json is simple wrapper script around the Python standard library csv and json modules for converting CSV formatted data to JSON.

The script reads CSV formatted data and outputs it into an JSON array of objects. By default the values in the first row of the CSV data will be used as fieldnames.

csv2json

A command-line tools and module to convert csv to json

PyPI

5- CSV to JSON (Python Script)

This is a working script that will convert a CSV file to valid JSON using Python. It is a working script and will soon be more robust.

GitHub - katiemarriner/csvtojson: CSV to JSON with Python

CSV to JSON with Python. Contribute to katiemarriner/csvtojson development by creating an account on GitHub.

GitHubkatiemarriner

6- csv2json

Clients were sending me XLS files but my webs consume JSONs. So I needed to convert them to JSON easily from command-line...

GitHub - darwin/csv2json: A gem useful for converting CSV files to JSON from command-line

A gem useful for converting CSV files to JSON from command-line - darwin/csv2json

GitHubdarwin

7- convert-csv-to-json (NPM)

This library allows anyone to Converts csv files to JSON files with Node.js.

GitHub - iuccio/csvToJson: Convert CSV file to JSON

Convert CSV file to JSON. Contribute to iuccio/csvToJson development by creating an account on GitHub.

GitHubiuccio

8- Fast-csv-to-json (Rust)

A simple CLI tool for converting CSV file content to JSON.

GitHub - ming900518/csv-to-json: A simple CLI tool for converting CSV file content to JSON.

A simple CLI tool for converting CSV file content to JSON. - ming900518/csv-to-json

GitHubming900518

9- csv2json (Swift)

This app is an open-source free Command-line tool to convert csv to json, written in Swift.

GitHub - hadig/csv2json: Command-line tool to convert csv to json, written in Swift.

Command-line tool to convert csv to json, written in Swift. - hadig/csv2json

GitHubhadig