This is the simplest hit counter I could imagine (well, almost). Every time a 
page is requested, it adds one to the count. The display is not an image, just 
text. There is no javascript to hit some third-party server, no tracking, no 
distinction among pages: just an old-fashioned site counter CGI, implemented in 
WordPress. The plugin stores its count in its own MySQL table.
Once the plugin is installed (described below), you can display the count by 
putting code like this somewhere on your page:
<pre><code><?= simplehitcounter_hit(); ?>
</code></pre>
That will both increment the counter and display its value. There is no method 
for getting the value without incrementing it. I suppose I could write such a 
thing if anyone likes.
There is a minor race condition. First the plugin updates the database by one 
(atomically), then it queries for the current count. Therefore in heavy traffic 
it is possible for two updates to happen before either select. In that case, 
the counter will correctly increment, but the number displayed may be the same 
for each user, representing the total page hits. As far as I can tell, this 
race condition is inevitable without locking the table. It seems trivial 
enough, though I guess you should be warned if you run a contest to give away a 
free car to the 1,000,000th user.
By default the plugin keeps its data in a table called <code>wp_simplehitcounter_hits</code>. 
You can change this by editing the <code>simplehitcounter.php</code> file.

Simple Hit Counter

Prints a count of the number of hits your blog has received, tracked in the 
database.

SandyRig

As the name suggests, it’s a very simple Hit Counter that counts the number of Unique Visitors and Page-views. It’s very light weight so it doesn’t strain your site or cause render blocking.
You can show either Unique Visitors count or Page-views count anywhere on the site using widgets or shortcode. You can also add/show both Counters by using two copies of the widget or the shortcode.
Note: It keeps counting even when you have no widget or shortcode active. To completely disable the counter you have to disable the plugin.
<h4>Features</h4>
<ul>
<li>AJAX based counter ignores most bots or crawlers</li>
<li>Monthly and weekly graph in admin</li>
<li>Show the Unique Visitors, Page-views count or both</li>
<li>Ability to reset the counter to any number any time</li>
<li>Can be shown anywhere on the site using Widgets and Shortcode</li>
<li>Counter works and shows data in admin even when no widget or short-code is active</li>
</ul>
<h4>SHORTCODES</h4>
[srs_total_visitors] for Unique Visitors 
[srs_total_pageViews] for Page-views
<a href="https://atif.rocks/srs-simple-hits-counter/" rel="nofollow ugc">DEMO</a>

SRS Simple Hits Counter

Simple plugin to count and show a total number of hits (Unique visitors or page-views) to the site without using any third party code.

Simple Hit Counter vs SRS Simple Hits Counter