When you click on the button the input loose the focuse that why you should use a flag focused_index that raise the index of the last focuse input then target the next index using :
$('.textboxfield').eq(focused_index+1).focus();
NOTE : Use autofocus attribute to make the first input focusable by default.
$(document).ready(function() {
var focused_index = 0;
$("#nextInput").click(function() {
$('.textboxfield').eq(focused_index+1).focus();
});
$(".textboxfield").focus(function() {
focused_index = $(".textboxfield").index($(this));
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="col-md-6 col-sm-6" style="padding-top: 25px; font-weight: bold;" id="outOffDiv">
<a href="#" class="outoff previous round" id="previousInput">‹</a> <span id="currentField">1</span> out of <span id="totalFileds">16</span>
<a href="#" class="outoff next round" id="nextInput">›</a>
</div>
<br/>
<input class="textboxfield" id="name" name="name" placeholder="Name" tabindex="1" value="" type="text" autofocus>
<br/>
<input class="textboxfield" id="age" name="age" placeholder="Age" tabindex="2" value="" type="text">
<br/>
<input class="textboxfield" id="address" name="address" placeholder="Address" tabindex="3" value="" type="text">
<br/>
<input class="textboxfield" id="state" name="state" placeholder="State" tabindex="4" value="" type="text">
html code. Because thejs functionwill depend on yourhtml structure