Prepend https to URL if necessary

Posted on October 10, 2021

This javascript function prepends the https:// chunk to a provided URL only if missing:

var prependHTTP =  url => {
  url = decodeURIComponent(url)
  if (!/^(?:f|ht)tps?\:\/\//.test(url)) {
    url = 'https://' + url
  }
  return url
}

This way, we can be sure that the final URL contains the https protocol:

prependHTTP('https://www.google.com') //'https://www.google.com'
prependHTTP('www.google.com') //'https://www.google.com'