$ npm install -g npmrm

$ npmrm ls

  yarn --- https://registry.yarnpkg.com
  npm ---- https://registry.npmjs.org/
  cnpm --- http://r.cnpmjs.org/
* taobao - https://registry.npm.taobao.org/
  nj ----- https://registry.nodejitsu.com/
  rednpm - http://registry.mirror.cqupt.edu.cn/
  npmMirror  https://skimdb.npmjs.com/registry/
  edunpm - http://registry.enpmjs.org/
  tencent  https://mirrors.cloud.tencent.com/npm/

$ npmrm use cnpm

    Registry has been set to: http://r.cnpmjs.org/

Usage: npmrm [options] [command]

Options:
  -V, --version                output the version number
  -h, --help                   display help for command

Commands:
  ls                           List all the registries
  current                      Show current registry name
  add <registry> <url> [home]  Add one custom registry
  use <registry>               Change registry to registry
  del <registry>               Delete one custom registry
  home <registry> [browser]    Open the homepage of registry with optional browser
  test [registry]              Show response time for specific or all registries
  help                         Print this help