npm command-line interface

# npm-explain

Explain installed packages

## Table of contents

- Synopsis
- Description
- Configuration

- json

- See Also

### Synopsis

    npm explain <folder | specifier>

    alias: why

### Description

This command will print the chain of dependencies causing a given package to be installed in the current project.

Positional arguments can be either folders within `node_modules`, or `name@version-range` specifiers, which will select the dependency relationships to explain.

For example, running `npm explain glob` within npm’s source tree will show:

    glob@7.1.6
    node_modules/glob
      glob@"^7.1.4" from the root project

    glob@7.1.1 dev
    node_modules/tacks/node_modules/glob
      glob@"^7.0.5" from rimraf@2.6.2
      node_modules/tacks/node_modules/rimraf
        rimraf@"^2.6.2" from tacks@1.3.0
        node_modules/tacks
          dev tacks@"^1.3.0" from the root project

To explain just the package residing at a specific folder, pass that as the argument to the command. This can be useful when trying to figure out exactly why a given dependency is being duplicated to satisfy conflicting version requirements within the project.

    $ npm explain node_modules/nyc/node_modules/find-up
    find-up@3.0.0 dev
    node_modules/nyc/node_modules/find-up
      find-up@"^3.0.0" from nyc@14.1.1
      node_modules/nyc
        nyc@"^14.1.1" from tap@14.10.8
        node_modules/tap
          dev tap@"^14.10.8" from the root project

### Configuration

#### json

- Default: false
- Type: Boolean

Show information in JSON format.

### See Also

- npm config
- npmrc
- npm folders
- npm ls
- npm install
- npm link
- npm prune
- npm outdated
- npm update