jtcsv - JSON <-> CSV toolkit for Node.js and browser

Fast JSON <-> CSV conversion with streaming helpers, NDJSON/TSV support, and optional integrations.

Features

• JSON <-> CSV conversion with security defaults
• Streaming helpers and async iterator API
• NDJSON and TSV helpers
• Browser bundle with Web Worker helpers
• Optional plugin system and framework adapters
• CLI and optional TUI

Installation

npm install jtcsv

Optional add-ons

npm install @jtcsv/tui
npm install @jtcsv/excel exceljs
npm install @jtcsv/validator

Quick start (Node.js)

const { jsonToCsv, csvToJson } = require('jtcsv');

const data = [
  { id: 1, name: 'John', email: 'john@example.com' },
  { id: 2, name: 'Jane', email: 'jane@example.com' }
];

const csv = jsonToCsv(data, { delimiter: ',', includeHeaders: true });
const json = csvToJson(csv, { delimiter: ',', parseNumbers: true });

console.log(csv);
console.log(json);

Async iterator

const { csvToJsonIterator } = require('jtcsv');

const csv = 'id,name\n1,Jane\n2,John';
for await (const row of csvToJsonIterator(csv, { fastPathMode: 'compact' })) {
  console.log(row);
}

Browser usage

• Bundler: import { csvToJson, jsonToCsv } from 'jtcsv/browser';
• CDN UMD: https://cdn.jsdelivr.net/npm/jtcsv/dist/jtcsv.umd.js
• CDN ESM: https://cdn.jsdelivr.net/npm/jtcsv/dist/jtcsv.esm.js

See README-browser.md for full browser API and worker helpers.

CLI

npx jtcsv csv-to-json input.csv output.json
npx jtcsv json-to-csv input.json output.csv
npx jtcsv stream csv-to-json big.csv output.json
npx jtcsv batch json-to-csv "data/*.json" output/

# optional TUI
npx jtcsv tui

See CLI.md for full command list and options.

Demos

Run these from the repo root:

# Express API demo
npm run demo

# Web demo (Vite dev server on http://localhost:3000)
npm run demo:web

# Preview built demo
npm run demo:serve

From inside demo/ use:

npm run dev
npm run preview
npm run serve

Plugin system

The plugin-enabled API is exported from jtcsv/plugins.

const { create } = require('jtcsv/plugins');

const jtcsv = create();
jtcsv.use('my-plugin', { name: 'My Plugin', version: '1.0.0' });

See README-PLUGINS.md and plugins/README.md for integrations.

Development

Run from the repo root:

npm test
npm run test:coverage
npm run build

License

MIT. See LICENSE.