-Code Snippets by Code Snippets Pro

Code Snippets is being used on the following sites: kyeyes.org, greenhouse17.org, and chefNoahHester.com. This plugin is used on specific pages vs all pages. Code Snippets is an easy, clean and simple way to run code snippets on your site. It removes the need to add custom snippets to your theme’s functions.php file.

Link to plugin: https://wordpress.org/plugins/code-snippets/

Free Version: Yes, Plan starts at $39 per year for one website.

-WP Code Box 

One of the top rated Code Snippet Plugins. It supports basically all themes and also supports things like WooCommerce. It’s compatible with all languages and can be used on all pages in a reusable code block that can be copied infinitely or specific to a particular page.

Link to plugin: https://wpcodebox.com/

Free Version: No, License price starts at $29 for one domain.

-Advanced Scripts

Advanced Scripts is the best scripts manager on the market. Besides PHP, CSS, and Javascript, you can also write SCSS and LESS code, use custom hooks, and all of that in a better interface. Has many built in custom methods as well as the ability to load external resources.

Link to plugin: https://www.cleanplugins.com/products/advanced-scripts/

Free Version: No, Single site license costs $19.99.