JavaScript – Count Number of Visitor for Website

I am new to JavaScript, How do i increment the number whenever the page is refreshed on the browser. Client Implementation only 🙂

Here is my html code:

<div id="CounterVisitor">
          <span class="counter-item">0</span>
          <span class="counter-item">0</span>
          <span class="counter-item">1</span>
          <span class="counter-item">1</span>
          <span class="counter-item">8</span>
          <span class="counter-item">4</span>
</div>

My JavaScript:

var counter = 001184;
var newnum = 001184 + 1;

var el = document.getElementsByClassName("counter-item");
el.innerHTML = newnum;

This is how the result will look like when i refresh the browser, but it is static for now.