npm

internal-ip

Get your internal IP address

default-uid

Get the system default UID

downgrade-root

Try to downgrade the permissions of a process with root privileges

public-ip

Get your public IP address — very fast!

dnsbl

Query DNS-based blackhole lists

root-hints

Provides IP addresses of the DNS root servers, also known as 'root hints'.

is-online

Check if the internet connection is up

untildify

Convert a tilde path to an absolute path: `~/dev` → `/Users/sindresorhus/dev`

detect-engine

Detect whether you're running on node.js or io.js

port-numbers

Get information on network port numbers and services, based on IANA's public listing

oui

Look up MAC addresses for their vendor in the IEEE OUI database

tcpie

Ping any TCP port

droppy

Self-hosted file storage

download

Download and extract files

expect-telnet

telnet automation through expect-send sequences, like in Tcl

fix-path

Fix the $PATH on macOS and Linux when run from a GUI app

shell-path

Get the $PATH from the shell

file-extension

Get the extension of a given filename or path

cidr-range

Get an array of IP addresses for a given CIDR range

rebirth

Restart a node process from within itself

is-reachable

Check if servers are reachable

is-online-cli

Check if the internet connection is up

uppie

Cross-browser directory and multi-file upload library

is-public-domain

Check if a domain is public

is-port-reachable

Check if a local or remote port is reachable