# package-json [](https://travis-ci.org/sindresorhus/package-json)
> Get metadata of a package from the npm registry
## Install
```
$ npm install package-json
```
## Usage
```js
const packageJson = require('package-json');
(async () => {
console.log(await packageJson('ava'));
//=> {name: 'ava', ...}
// Also works with scoped packages
console.log(await packageJson('@sindresorhus/df'));
})();
```
## API
### packageJson(packageName, options?)
#### packageName
Type: `string`
Name of the package.
#### options
Type: `object`
##### version
Type: `string`
Default: `latest`
Package version such as `1.0.0` or a [dist tag](https://docs.npmjs.com/cli/dist-tag) such as `latest`.
The version can also be in any format supported by the [semver](https://github.com/npm/node-semver) module. For example:
- `1` - Get the latest `1.x.x`
- `1.2` - Get the latest `1.2.x`
- `^1.2.3` - Get the latest `1.x.x` but at least `1.2.3`
- `~1.2.3` - Get the latest `1.2.x` but at least `1.2.3`
##### fullMetadata
Type: `boolean`
Default: `false`
By default, only an abbreviated metadata object is returned for performance reasons. [Read more.](https://github.com/npm/registry/blob/master/docs/responses/package-metadata.md)
##### allVersions
Type: `boolean`
Default: `false`
Return the [main entry](https://registry.npmjs.org/ava) containing all versions.
##### registryUrl
Type: `string`
Default: Auto-detected
The registry URL is by default inferred from the npm defaults and `.npmrc`. This is beneficial as `package-json` and any project using it will work just like npm. This option is **only** intended for internal tools. You should **not** use this option in reusable packages. Prefer just using `.npmrc` whenever possible.
##### agent
Type: `http.Agent | https.Agent | object | false`
Overwrite the `agent` option that is passed down to [`got`](https://github.com/sindresorhus/got#agent). This might be useful to add [proxy support](https://github.com/sindresorhus/got#proxies).
### packageJson.PackageNotFoundError
The error thrown when the given package name cannot be found.
### packageJson.VersionNotFoundError
The error thrown when the given package version cannot be found.
## Authentication
Both public and private registries are supported, for both scoped and unscoped packages, as long as the registry uses either bearer tokens or basic authentication.
## Related
- [package-json-cli](https://github.com/sindresorhus/package-json-cli) - CLI for this module
- [latest-version](https://github.com/sindresorhus/latest-version) - Get the latest version of an npm package
- [pkg-versions](https://github.com/sindresorhus/pkg-versions) - Get the version numbers of a package from the npm registry
- [npm-keyword](https://github.com/sindresorhus/npm-keyword) - Get a list of npm packages with a certain keyword
- [npm-user](https://github.com/sindresorhus/npm-user) - Get user info of an npm user
- [npm-email](https://github.com/sindresorhus/npm-email) - Get the email of an npm user
---