How to Use Window.Prompt in Javascript

From WikiHTP

An easy way to get an input from a user is by using the prompt() method. Syntax

prompt(text, [default]);
  • text: The text displayed in the prompt box.
  • default: A default value for the input field (optional).


var age = prompt("How old are you?");
console.log(age); // Prints the value inserted by the user

If the user clicks the OK button, the input value is returned. Otherwise, the method returns Null.

The return value of prompt is always a string unless the user clicks Cancel, in which that case it returns Null. Safari is an exception to that when the user clicks Cancel, the function returns an empty string. From there, you can convert the return value to another type, such as an integer.


  • While the prompt box is displayed, the user is prevented from accessing other parts of the page, since dialog boxes are modal windows.
  • Starting with Chrome 46.0 this method is blocked inside an <iframe> unless its sandbox attribute has the value allow-modal.

About This Tutorial

This page was last edited on 28 January 2019, at 06:37.