This javascript cut & paste code snippet adds a dollar sign and commas in the proper places to convert a number into its proper U.S. currency format. This function automatically occurs when the user clicks the button, or when they finish entering the money amount (when cursor clicks into the next field).

Insert this code into your HEAD of HTML

<!-- // == This Script Free To Use Providing This Notice Remains == // // == This Script Has Been Found In The http://www.DesignerWiz.com Javascript Public Archive Library == // // == NOTICE: Though This Material May Have Been In A Public Depository, Certain Author Copyright Restrictions May Apply == // --><script language="JavaScript" type="text/javascript"> <!-- Begin function checkNum(data) { // checks if all characters var valid = "0123456789."; // are valid numbers or a "." var ok = 1; var checktemp; for (var i=0; i<data.length; i++) { checktemp = "" + data.substring(i, i+1); if (valid.indexOf(checktemp) == "-1") return 0; } return 1; } function dollarAmount(form, field) { // idea by David Turley Num = "" + eval("document." + form + "." + field + ".value"); dec = Num.indexOf("."); end = ((dec > -1) ? "" + Num.substring(dec,Num.length) : ".00"); Num = "" + parseInt(Num); var temp1 = ""; var temp2 = ""; if (checkNum(Num) == 0) { alert("This does not appear to be a valid number. Please try again."); } else { if (end.length == 2) end += "0"; if (end.length == 1) end += "00"; if (end == "") end += ".00"; var count = 0; for (var k = Num.length-1; k >= 0; k--) { var oneChar = Num.charAt(k); if (count == 3) { temp1 += ","; temp1 += oneChar; count = 1; continue; } else { temp1 += oneChar; count ++; } } for (var k = temp1.length-1; k >= 0; k--) { var oneChar = temp1.charAt(k); temp2 += oneChar; } temp2 = "$" + temp2 + end; eval("document." + form + "." + field + ".value = '" + temp2 + "';"); } } // End --></script>

Insert this code into your BODY section

<center> <form name=commaform>Enter a number then click the button: <input type=text name=input size=10 value=""> <input type=button value="Convert" onclick="dollarAmount(this.form.name, 'input')"> <br><br> or enter a number and click another field: <input type=text name=input2 size=10 value="" onBlur="dollarAmount(this.form.name, this.name)"> </form>