Creating a Child Theme in WordPress: Code Examples

When customizing a WordPress theme, it’s essential to use a child theme to ensure that your modifications remain intact during theme updates. In this post, I will guide you through the process of creating a child theme in WordPress, providing code examples along the way.

Let’s get started!

1. What is a Child Theme?

A. Definition and purpose of a child theme

A child theme in WordPress is a theme that inherits the functionality and styling of its parent theme. It allows you to make modifications to a theme without directly editing its core files. Instead, you create a separate theme that acts as a child of the parent theme, which retains all the features and updates of the parent theme while allowing you to customize its appearance and functionality.

The purpose of a child theme is to provide a safe and efficient way to make customizations to a WordPress theme.

B. Benefits of using a child theme

  • Preserves Parent Theme Updates: When you update the parent theme, any modifications made directly to its files will be overwritten. By using a child theme, you can ensure that your customizations remain intact even when the parent theme is updated.
  • Easy Customization: With a child theme, you have full control over the appearance and functionality of your WordPress site. You can modify templates, stylesheets, and functions without affecting the parent theme, allowing you to create a unique design and tailor the theme to your specific needs.
  • Separation of Concerns: By keeping your customizations separate from the parent theme, it becomes easier to manage and organize your code. This separation allows you to focus on the specific changes you want to make without cluttering the original theme files.
  • Enhanced Stability and Security: Child themes provide a layer of protection against errors or conflicts that may arise from modifying the parent theme directly. If something goes wrong with your customizations, you can easily revert to the parent theme or troubleshoot without affecting the entire site.
  • Learning and Experimentation: Creating a child theme allows you to explore WordPress theme development. You can experiment with different modifications, learn from the existing theme’s code, and gain hands-on experience with theme development practices.

2. Setting up the Child Theme

A. Create a New Directory for Your Child Theme

  • In your WordPress installation, navigate to the wp-content/themes directory.
  • Create a new folder with a unique name for your child theme. For example: mytheme-child.

B. Create a New Stylesheet for Your Child Theme

  • Inside the child theme folder, create a new file named style.css.
  • Open the style.css file in a text editor.

C. Add the Following Information to Your Child Theme’s Stylesheet

Theme Name: MyTheme Child
Theme URI: Theme uri
Description: Child theme for MyTheme
Author: Your name
Author URI: Website or profile URL
Template: Parent theme
Version: 1.0.0
  • Replace MyTheme Child with the desired name of your child theme.
  • Replace the Theme uri with the URL of your parent theme (if applicable).
  • Add a brief description of your child theme in the Description field.
  • Replace Your name with your name or the name of your organization.
  • Add your website or profile URL in the Author URI field.
  • Replace mytheme with the directory name of your parent theme.
  • Set the version number according to your child theme’s initial version.

D. Enqueue the parent Theme’s Stylesheet

  • Open the functions.php file of your child theme (if it doesn’t exist, create a new file named functions.php in the child theme folder).
  • Add the following code to the functions.php file:
function enqueue_child_theme_styles() {
   wp_enqueue_style( 'parent-style', get_template_directory_uri() . '/style.css' );
add_action( 'wp_enqueue_scripts', 'enqueue_child_theme_styles' );

3. Modifying Templates

When customizing a WordPress theme using a child theme, you may want to make changes to specific template files. Here’s a step-by-step guide on how to modify templates:

A. Identify the template files you want to modify

  • Analyze your parent theme and determine which template files control the elements you want to modify.
  • Common template files include header.php, footer.php, index.php, single.php, page.php, and so on.

B. Copy the template file from the parent theme to the child theme

  • In your child theme directory, create a new folder (if not already created) and name it template-parts.
  • Inside the template-parts folder, create a file structure that mirrors the structure of the parent theme.
  • Locate the template file you want to modify in the parent theme’s directory.
  • Copy the template file from the parent theme and paste it into the corresponding folder within the template-parts directory in the child theme.

C. Customize the copied template file as needed

  • Open the copied template file in a text editor.
  • Make the desired modifications to the HTML, CSS, or PHP code within the file.
  • You can add, remove, or modify elements, styles, and functionality to suit your needs.
  • Save the changes to the template file.

By copying and modifying the template files in your child theme, you ensure that your modifications won’t be overwritten when the parent theme is updated. WordPress will automatically prioritize the template files in the child theme over those in the parent theme.

4. Adding Custom CSS

A. Create a new CSS file in your child theme

  • Within your child theme directory, create a new file and name it something like custom-style.css.
  • You can use any text editor to create this file.

B. Add your custom CSS rules and styles

  • Open the custom-style.css file in your text editor.
  • Write your custom CSS rules and styles in this file.
  • For example, let’s say you want to change the font color of the headings to red:
/* custom-style.css */
h1, h2, h3, h4, h5, h6 {
  color: red;

C. Enqueue the custom CSS file in the child theme

  • Open the functions.php file of your child theme in a text editor.
  • Add the following code to enqueue the custom CSS file:
function enqueue_child_theme_styles() {
  wp_enqueue_style( 'child-style', get_stylesheet_directory_uri() . '/custom-style.css' );
add_action( 'wp_enqueue_scripts', 'enqueue_child_theme_styles' );

This code registers and enqueues the custom-style.css file within the child theme.

D. Save the changes and upload the child theme

  • Save the changes to the custom-style.css and functions.php files.
  • Upload the updated child theme directory to your WordPress installation.

Note: Make sure to follow best practices for writing CSS, such as using appropriate selectors and maintaining proper indentation and organization for better readability and maintenance of your styles.

5. Overriding Parent Theme Functions

Overriding parent theme functions in a child theme allows you to modify the behavior of specific functions without directly editing the parent theme’s files

A. Identify the functions you want to override

  • Determine which functions from the parent theme you want to modify or extend. These functions can be found in the parent theme’s files or in its documentation.

B. Override or modify the parent theme’s functions

Inside the functions.php file, add your custom code to override or modify the desired functions. For example:

function my_custom_function() {
    // Your custom code here
    // This will override the parent theme's function with the same name

Note: Remember to consider the function’s original purpose and any dependencies it may have. Test your modifications thoroughly to ensure they work as intended.