Copy Text to Clipboard (HTML + JavaScript)

<!-- The text field -->
<input type="text" value="Hello World" id="myInput">

<!-- The button used to copy the text -->
<button onclick="myFunction()">Copy text</button>

<script>
function myFunction() {
/* Get the text field */
var copyText = document.getElementById("myInput");

/* Select the text field */
copyText.select();

/* Copy the text inside the text field */
document.execCommand("copy");

/* Alert the copied text */
alert("Copied the text: " + copyText.value);
}
</script>