How to allow only numeric (0-9) in HTML inputbox using jQuery?

^{Note: This is an updated answer. Comments below refer to an old version which messed around with keycodes.}

jQuery

Try it yourself on JSFiddle.

There is no native jQuery implementation for this, but you can filter the input values of a text <input> with the following inputFilter plugin (supports Copy+Paste, Drag+Drop, keyboard shortcuts, context menu operations, non-typeable keys, the caret position, different keyboard layouts, and all browsers since IE 9):

// Restricts input for the set of matched elements to the given inputFilter function.
(function($) {
  $.fn.inputFilter = function(inputFilter) {
    return this.on("input keydown keyup mousedown mouseup select contextmenu drop", function() {
      if (inputFilter(this.value)) {
        this.oldValue = this.value;
        this.oldSelectionStart = this.selectionStart;
        this.oldSelectionEnd = this.selectionEnd;
      } else if (this.hasOwnProperty("oldValue")) {
        this.value = this.oldValue;
        this.setSelectionRange(this.oldSelectionStart, this.oldSelectionEnd);
      } else {
        this.value = "";
      }
    });
  };
}(jQuery));

You can now use the inputFilter plugin to install an input filter:

$(document).ready(function() {
  $("#myTextBox").inputFilter(function(value) {
    return /^\d*$/.test(value);    // Allow digits only, using a RegExp
  });
});

See the JSFiddle demo for more input filter examples. Also note that you still must do server side validation!

Pure JavaScript (without jQuery)

jQuery isn't actually needed for this, you can do the same thing with pure JavaScript as well. See this answer.

HTML 5

HTML 5 has a native solution with <input type="number"> (see the specification), but note that browser support varies:

• Most browsers will only validate the input when submitting the form, and not when typing.
• Most mobile browsers don't support the step, min and max attributes.
• Chrome (version 71.0.3578.98) still allows the user to enter the characters e and E into the field. Also see this question.
• Firefox (version 64.0) and Edge (EdgeHTML version 17.17134) still allow the user to enter any text into the field.

Try it yourself on w3schools.com.

Here is the function I use:

// Numeric only control handler
jQuery.fn.ForceNumericOnly =
function()
{
    return this.each(function()
    {
        $(this).keydown(function(e)
        {
            var key = e.charCode || e.keyCode || 0;
            // allow backspace, tab, delete, enter, arrows, numbers and keypad numbers ONLY
            // home, end, period, and numpad decimal
            return (
                key == 8 || 
                key == 9 ||
                key == 13 ||
                key == 46 ||
                key == 110 ||
                key == 190 ||
                (key >= 35 && key <= 40) ||
                (key >= 48 && key <= 57) ||
                (key >= 96 && key <= 105));
        });
    });
};

You can then attach it to your control by doing:

$("#yourTextBoxName").ForceNumericOnly();

Inline:

<input name="number" onkeyup="if (/\D/g.test(this.value)) this.value = this.value.replace(/\D/g,'')">

Unobtrusive style (with jQuery):

$('input[name="number"]').keyup(function(e)
                                {
  if (/\D/g.test(this.value))
  {
    // Filter non-digits from input value.
    this.value = this.value.replace(/\D/g, '');
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input name="number">

You could just use a simple JavaScript regular expression to test for purely numeric characters:

/^[0-9]+$/.test(input);

This returns true if the input is numeric or false if not.

or for event keycode, simple use below :

     // Allow: backspace, delete, tab, escape, enter, ctrl+A and .
    if ($.inArray(e.keyCode, [46, 8, 9, 27, 13, 110, 190]) !== -1 ||
         // Allow: Ctrl+A
        (e.keyCode == 65 && e.ctrlKey === true) || 
         // Allow: home, end, left, right
        (e.keyCode >= 35 && e.keyCode <= 39)) {
             // let it happen, don't do anything
             return;
    }

    var charValue = String.fromCharCode(e.keyCode)
        , valid = /^[0-9]+$/.test(charValue);

    if (!valid) {
        e.preventDefault();
    }

You can use on input event like this:

$(document).on("input", ".numeric", function() {
    this.value = this.value.replace(/\D/g,'');
});

But, what's this code privilege?

• It works on mobile browsers(keydown and keyCode have problem).
• It works on AJAX generated content too, because We're using "on".
• Better performance than keydown, for example on paste event.