<div style="border:1px solid gray;width: 450px; height:300px"> <h2>Add two textbox values without pressing anybuttons</h2> <input type="text" id="txtFirstNo" placeholder="pleaseenterFirst Number" onkeyup="sum()" /> <input type="text" id="txtSecondNo" placeholder="pleaseenterSecond Number" onkeyup="sum()" /> <br /> <div style="padding-top:10px"> Result: <input type="text" id="txtResult" /> </div></div>