How to check with javascript if connection is local host?

Question

I want to have a check in my javascript if the page loading up is on my local machine.

The reason why I want to do that is that when I developing I like to make sure

Answer 1

This one also covers some common cases where local network IPs start with 10.0. or 192.168. or Bonjour like domain ending on .local:

export function isLocalNetwork(hostname = window.location.hostname) {
  return (
    (['localhost', '127.0.0.1', '', '::1'].includes(hostname))
    || (hostname.startsWith('192.168.'))
    || (hostname.startsWith('10.0.'))
    || (hostname.endsWith('.local'))
  )
}