JS Morisset

Includes a 5 Star Rating in Schema markup:
<ol>
<li>If the Schema markup does not have an ‘aggregateRating’ property.</li>
<li>If Google allows an ‘aggregateRating’ property for that Schema type.</li>
</ol>
Google allows an ‘aggregateRating’ property for these Schema types and their sub-types:
<ul>
<li>Book</li>
<li>Course</li>
<li>Event</li>
<li>HowTo (includes Recipe)</li>
<li>LocalBusiness</li>
<li>Movie</li>
<li>Product</li>
<li>SoftwareApplication</li>
</ul>
If the Schema type in the Document SSO metabox is not one of these types (or one of their sub-types), then a 5 star rating cannot be added, as doing so would trigger an error in the Google search console. <a href="https://developers.google.com/search/docs/advanced/structured-data/review-snippet" rel="nofollow ugc">See Google’s Review snippet documentation for additional information.</a>

<h3>WPSSO Add Five Stars is a Fallback Solution</h3>
The Google’s Review Snippet technical guidelines reminds us to:
<blockquote>
<a href="https://developers.google.com/search/docs/advanced/structured-data/review-snippet#technical-guidelines" rel="nofollow ugc">Make sure the reviews and ratings you mark up are readily available to users from the marked-up page. It must be immediately obvious to users that the page has review content.</a>
</blockquote>
The WPSSO Add Five Stars add-on includes a 5 star rating if the document Schema markup does not already have an ‘aggregateRating’ property. It is always preferable to include actual ratings and reviews from your visitors and/or customers in the webpage. The WPSSO Add Five Stars add-on can be used in combination with any of the following third-party plugins and service APIs, or the <a href="https://wordpress.org/plugins/wpsso-ratings-and-reviews/" rel="ugc">WPSSO Ratings and Reviews</a> add-on.
Suggested Rating and Review Plugins and Services:
The <a href="https://wordpress.org/plugins/wpsso/" rel="ugc">WPSSO Core plugin</a> supports a selection of plugins that provide ratings and reviews:
<ul>
<li>WP-PostRatings</li>
<li>WP Product Review</li>
<li>Yotpo Social Reviews for WooCommerce</li>
<li>WooCommerce</li>
<li><a href="https://wordpress.org/plugins/wpsso-ratings-and-reviews/" rel="ugc">WPSSO Ratings and Reviews</a></li>
</ul>
The <a href="https://wpsso.com/" rel="nofollow ugc">WPSSO Core Premium plugin</a> also supports a selection of remote service APIs that provide ratings and reviews:
<ul>
<li>Judge.me (Ratings and Reviews)</li>
<li>Shopper Approved (Ratings and Reviews)</li>
<li>Stamped.io (Ratings and Reviews)</li>
</ul>
<h3>WPSSO Core Required</h3>
WPSSO Add Five Stars is an add-on for the <a href="https://wordpress.org/plugins/wpsso/" rel="ugc">WPSSO Core plugin</a>, which creates extensive and complete structured data to present your content at its best for social sites and search results – no matter how URLs are shared, reshared, messaged, posted, embedded, or crawled.

WPSSO Add Five Stars for Google Rich Snippets

Add a 5 star rating and review from the site organization if the Schema markup does not already have an 'aggregateRating' property.

Jayce53

Run all the pages on your blog through Google’s <a href="http://www.google.com/webmasters/tools/richsnippets" rel="nofollow ugc">Rich Snippet Test Tool</a> with a single click.
When Google implemented <a href="http://support.google.com/webmasters/bin/answer.py?hl=en&answer=99170" rel="nofollow ugc">Rich Snippets</a> they 
also provided a test tool so you can verify that a page is correctly formatted and see how Google will show your page in their search results.
That’s great, but… if you need to check more than a few pages, it’s a time consuming and tedious task.
EasySnippet makes it easy to check every page on your WordPress blog with just one click.
Works for all rich snippet markup: recipes, reviews, products, people, music and more.
Requires PHP 5+

Rich Snippet Site Report

Run all the pages on your blog through Google's Rich Snippet Test Tool with a single click.

WPSSO Add Five Stars for Google Rich Snippets vs Rich Snippet Site Report