What is a package.json file?

A package.json is the manifest file for Node.js and JavaScript projects. It defines your project's name, version, dependencies, scripts, license, and other metadata. npm, pnpm, and Yarn all rely on it to install packages and run scripts.

Which package.json fields are required?

Only `name` and `version` are required by the npm registry when publishing. For private projects used locally, even those are optional. However, adding `description`, `license`, `author`, and `scripts` is strongly recommended.

What is the difference between 'main', 'module', and 'exports'?

`main` is the CommonJS (CJS) entry point used by Node.js `require()`. `module` is an unofficial field used by bundlers like webpack and Rollup for the ESM version. `exports` is the modern standard that maps package entry points for both CJS and ESM and takes precedence over `main` in Node.js 12+.

Should I set 'type' to 'module' or 'commonjs'?

Set `"type": "module"` if your source files use ES module syntax (`import`/`export`). Set it to `"commonjs"` (or omit it, since that's the default) if you use `require()`/`module.exports`. Mixing both is possible using `.mjs`/`.cjs` file extensions.

Is the generated package.json valid?

Yes. The generator only includes fields with values you've filled in, producing clean, valid JSON. You can validate it further at npmjs.com or with `npm pkg fix` in your project directory.

Can I use this without npm?

Absolutely. The generated package.json works with pnpm, Yarn, Bun, and any other package manager that follows the npm manifest specification.

Free Developer Tool

Generate Perfect
package.json Files

Stop guessing field names. Fill in the form, pick your license, add your scripts, and get a ready-to-use package.json in seconds — no login, no installs.

📦

All Fields Covered

Name, version, description, keywords, author, license, main, module, exports, engines, and more — all in one form.

⚡

Script Builder

Pick from common npm scripts (dev, build, test, lint, type-check) and add custom ones with a single click.

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100% Client-Side

Everything runs in your browser. Nothing is sent to any server. Copy or download your package.json instantly.

Package Info

Name *

Version *

Description

Keywords

Private package (won't be published to npm)

Author & License

Author Name

Author Email

Author URL

License

Links

Homepage

Repository (git URL)

Bugs URL

Entry Points

Module type

main (CJS)

module (ESM)

types / typings

Include exports field (modern Node.js)

engines

Format: runtime @ semver — e.g. node @ >=18.0.0

Scripts

Common scripts — click to toggle:

Output

package.json

{
  "version": "1.0.0",
  "license": "MIT",
  "main": "./dist/index.js",
  "module": "./dist/index.mjs",
  "types": "./dist/index.d.ts",
  "engines": {
    "node": ">=18.0.0"
  }
}

100% client-side — nothing is sent to any server.

Frequently Asked Questions

Everything you need to know about Package.json Generator.

Generate Perfectpackage.json Files