WordPress is one of the most powerful blog platforms out there. One of its strength is the ability to allow post authors to assign custom fields to a post. This arbitrary extra information is known as meta-data and can be added using the Custom Fields box under the content editor of writing post screen. The problem is that adding these meta data handy is not a good idea for most users because they have to know what are the meta key and type of its value. It’s better when developers create a custom meta box that can show which information is needed and give some explanations to users. In this tutorial, we’ll see how to creating a better meta box in WordPress post editing page.

Before we start, make sure that you theme has functions.php file. All of our code will be pasted into this file. And our result will be like this (click to enlarge):