Random Password Generator In JavaScript

An online app to generate random strong passwords with just one click. Written in HTML CSS & JavaScript. Without third-party libraries.

How to use it:

1. Create an input file to place the generated password strings.

<input type="text">

2. Create a button to generate a strong password.

<button>Generate Password</button>

3. Create Copy buttons inside the password field. Requires Font Awesome Iconic Font in this example.

<span class="far fa-copy" onclick="copy()"></span>
<span class="fas fa-copy" onclick="copy()"></span>

4. The main script to enable the password generator.

const display = document.querySelector("input"),
      button = document.querySelector("button"),
      copyBtn = document.querySelector("span.far"),
      copyActive = document.querySelector("span.fas");
let chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()_+~`|}{[]:;?><,./-=";
button.onclick = ()=>{
  let i,
  randomPassword = "";
  copyBtn.style.display = "block";
  copyActive.style.display = "none";
  for (i = 0; i < 16; i++) {
    randomPassword = randomPassword + chars.charAt(
      Math.floor(Math.random() * chars.length)
    );
  }
  display.value = randomPassword;
}
function copy(){
  copyBtn.style.display = "none";
  copyActive.style.display = "block";
  display.select();
  document.execCommand("copy");
}