Vladimir Prelovac

The Yahoo! Exceptional Performance team recommends <a href="http://developer.yahoo.com/performance/rules.html#js_bottom" rel="nofollow ugc">placing scripts at the bottom of your page</a> because of the way browsers download components.
“The problem caused by scripts is that they block parallel downloads. The HTTP/1.1 specification suggests that browsers download no more than two components in parallel per hostname. If you serve your images from multiple hostnames, you can get more than two downloads to occur in parallel. While a script is downloading, however, the browser won’t start any other downloads, even on different hostnames.
In some situations it’s not easy to move scripts to the bottom. If, for example, the script uses document.write to insert part of the page’s content, it can’t be moved lower in the page. There might also be scoping issues. In many cases, there are ways to workaround these situations.”
WordPress default behavior is to load javascript in the page.
This plugin will move all javascript code to the footer if the plugins have <a href="http://www.prelovac.com/vladimir/best-practice-for-adding-javascript-code-to-wordpress-plugin" rel="nofollow ugc">declared javascript properly</a>.
Plugin by <a href="http://www.prelovac.com/vladimir" rel="nofollow ugc">Vladimir Prelovac</a>. Looking for <a href="http://www.prelovac.com/vladimir/services" rel="nofollow ugc">WordPress Services</a>?
<h3>License</h3>
This file is part of Footer JavaScript.
Footer JavaScript is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
Footer JavaScript is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with Footer JavaScript. If not, see <a href="http://www.gnu.org/licenses/" rel="nofollow ugc">http://www.gnu.org/licenses/</a>.

JavaScript to Footer

I used and face some of bad experience with it 

Can't give perfect result

This plugin automatically moves JavaScript code to page footer, speeding up page loading time.

Ajay

WebberZone

Do you want to customize your site with code but don’t want to edit your theme files or worry about losing your changes when you switch themes? Do you want to add analytics, site verification, custom CSS, or any other code to your site without using multiple plugins? Do you want complete control over where and when you display your code snippets on your site?
If you answered yes to any of the above questions, WebberZone Snippetz is the perfect plugin!
<a href="https://webberzone.com/plugins/add-to-all/" rel="nofollow ugc">WebberZone Snippetz</a> (formerly Add to All) is a simple yet powerful plugin that allows you to create and manage custom snippets of HTML, CSS, or JS code and add them to your header, footer, content, or feed. You can also choose where and when to display your snippets based on criteria such as post IDs, post types, categories, tags, and more.
WebberZone Snippetz comes with out-of-the-box support for Google Analytics and Statcounter. It lets you easily add meta tags to verify your site with Google, Bing, and Pinterest.
WebberZone Snippetz also enhances your site’s feed with a copyright notice and a link to the post. It also comes with many actions and filters to extend its functionality.
Here are some of the key features of WebberZone Snippetz:
<ul>
<li>Create custom snippets with HTML, CSS or JS code</li>
<li>Add snippets to your header, footer, content or feed</li>
<li>Choose where and when to display your snippets based on post IDs, post types, categories, tags, and more</li>
<li>Support for Google Analytics and Statcounter</li>
<li>Site verification for Google, Bing and Pinterest</li>
<li>No need to edit theme files or lose changes when switching themes</li>
</ul>
WebberZone Snippetz is the ultimate snippet manager for WordPress users who want to customize their site with code. Download it today and see the difference! 
WebberZone Snippetz is one of the many plugins developed by WebberZone. Check out our other plugins:
<ul>
<li><a href="https://wordpress.org/plugins/contextual-related-posts/" rel="ugc">Contextual Related Posts</a> – Display related posts on your WordPress blog and feed</li>
<li><a href="https://wordpress.org/plugins/top-10/" rel="ugc">Top 10</a> – Track daily and total visits on your blog posts and display the popular and trending posts</li>
<li><a href="https://wordpress.org/plugins/knowledgebase/" rel="ugc">Knowledge Base</a> – Create a knowledge base or FAQ section on your WordPress site</li>
<li><a href="https://wordpress.org/plugins/better-search/" rel="ugc">Better Search</a> – Enhance the default WordPress search with contextual results sorted by relevance</li>
<li><a href="https://wordpress.org/plugins/autoclose/" rel="ugc">Auto-Close</a> – Automatically close comments, pingbacks and trackbacks and manage revisions</li>
</ul>

WebberZone Snippetz – Header, Body and Footer manager

The ultimate snippet manager for WordPress. Create and manage custom HTML, CSS, or JS code snippets and control where and when they are displayed.

JavaScript to Footer vs WebberZone Snippetz – Header, Body and Footer manager