Woody Code Snippets: a handy plugin for adding code into your header and footer. You can also use it to register and run PHP functions and code. The premium version comes with cloud storage and syncs them with your sites.
Code Snippets: a PHP code snippet WordPress plugin that provides you with a graphical interface for managing snippets. You can also export snippets easily.
Head, Footer and Post Injections: a handy plugin for inserting code snippets into your site’s header and footer. You can also add them inside your posts. This plugin can execute conditional PHP code.
Insert PHP Code Snippet: this plugin lets you create shortcodes with PHP code snippets. You can use these snippets in your widgets.
Post Snippets: a code snippet management plugin for WordPress that lets you manage and run HTML and PHP code. Lets you have as many optional variables as you want for your shortcodes.
Snippeta: this app lets you collect and organize pieces of code that you use often. Your visitors can share links to your code snippets too.
Header Footer Code Manager: another plugin for managing scripts and styles on your website. You can choose where and on which devices your scripts load.
Your Shortcode: a visual builder for creating and managing your own WordPress shortcodes. Lets you maintain an unlimited number of shortcodes.
Raw HTML Snippets: this plugin lets you create a library of raw HTML snippets to insert into pages and posts.
Tracking Code Manager: a WordPress plugin for managing all your scripts and tracking in one page. Lets you easily choose the position of each code and exclude it on certain pages.
Have you found better code snippet managers for WordPress? Please share them here.