JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://knockoutjs.com/downloads/knockout-3.0.0.js"></script>
<span data-bind="text: Interval" ></span>
<input data-bind="numeric:Interval" />

JavaScript

ko.bindingHandlers.numeric = {
        init: function (element, valueAccessor) {
            var value = valueAccessor();
            $(element).on("keydown", function (event) {
                // Allow: backspace, delete, tab, escape, and enter
                if (event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || event.keyCode == 27 || event.keyCode == 13 ||
                    // Allow: Ctrl+A
                    (event.keyCode == 65 && event.ctrlKey === true) ||
                    // Allow: . ,
                    (event.keyCode == 188 || event.keyCode == 190 || event.keyCode == 110) ||
                    // Allow: home, end, left, right
                    (event.keyCode >= 35 && event.keyCode <= 39)) {
                    // let it happen, don't do anything
                    return;
                }
                else {
                    // Ensure that it is a number and stop the keypress
                    if (event.shiftKey || (event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105)) {
                        event.preventDefault();
                    }
                }
            });
            
            $(element).change(function () {
                value($(element).val());
            });
        }    
    };

ko.applyBindings({Interval: ko.observable()});