Ever wondered what goes on “under the hood” of a custom WordPress theme? If you’ve heard of Underscores (_s) but aren’t sure what it is—or why so many developers rely on it—you’re not alone.
Understanding Underscores is essential if you want to build flexible, reliable WordPress sites without starting from scratch.
In this article, you’ll discover exactly how Underscores powers WordPress theme development, why it matters, and practical steps to get started using it yourself.
Related Video
What is Underscores (_s) in WordPress?
Underscores (_s) is a highly regarded starter theme for WordPress. It’s designed as a clean foundation for developers to build their own custom themes. Think of it as a blank canvas—providing all the basic structure, files, and best practices you need to start, without unnecessary styling or features. This allows you to focus on design and functionality, not boilerplate code.
Underscores is the go-to choice for many WordPress professionals because it is lightweight, modular, and continuously updated to follow WordPress coding standards.
Why Use Underscores for WordPress Theme Development?
Using Underscores as your starting point brings several clear advantages:
- Saves Time: Skip repetitive setup and base files. You get a solid structure out of the box.
- Clean Code: It follows best practices, delivering secure, modern and readable code.
- Flexibility: There’s hardly any styling. Customize to match your vision without fighting existing code.
- Up-to-Date: Maintained by WordPress experts, so it always adopts the latest standards.
- Responsive Ready: Mobile-first structure so your theme works well on any device.
Key Features of Underscores
- Minimal Design: Very little CSS, so you aren’t forced into any specific design choices.
- HTML5 Templates: All templates use semantic HTML5.
- Accessibility Ready: Built with accessibility in mind to help your site work for everyone.
- Theme-Ready Files: Includes files for template parts, comments, widgets, and editor styles.
- Starter Templates: Comes with template tags, menu support, and sample customizer settings.
- SASS Integration: Optional SASS files for advanced, organized CSS.
Steps to Start Building a WordPress Theme with Underscores
Ready to jump in? Here’s a simple walkthrough to get you started with Underscores.
1. Generate Your Custom Underscores Theme
Underscores lets you generate a personalized version.
- Go to the Underscores theme generator (typically on their official site).
- Enter your theme’s name. This automatically customizes the text domain and functions for you.
- Download the theme ZIP file.
2. Install the Theme into WordPress
- Log into your WordPress dashboard.
- Navigate to:
- Appearance → Themes → Add New → Upload Theme.
- Select your downloaded ZIP file and install it.
- Activate the theme.
3. Understand the Starter Files
Underscores provides a clear structure:
style.css– Main stylesheet and theme info.functions.php– Theme setup, scripts, and custom functions.index.php,header.php,footer.php,sidebar.php– Main template parts.page.php,single.php,archive.php,404.php,search.php– Page templates./incfolder – For reusable functions and extras./template-parts– For organizing reusable sections.
4. Begin Customizing
Here’s what you’ll typically want to do:
- Modify CSS: Rewrite
style.cssto bring your unique design. Optionally, set up SASS for advanced workflows. - Edit Templates: Open the templates and adjust layouts as needed.
- Develop Functions: Add or tweak features in
functions.php. - Set Up Menus, Widgets, and Sidebars: Register your theme locations and features.
- Test Responsiveness: Use tools and browsers to ensure your theme looks great everywhere.
Benefits of Using Underscores
Let’s look deeper at what makes Underscores such a powerful choice for theme development.
1. Developer-Friendly Structure
There’s no clutter. Everything is where you’d expect, using standard names and WordPress conventions. You spend less time trying to decipher someone else’s logic.
2. Best Practices Built-In
All code in Underscores is clean, readable, and up-to-date. This makes it easier to maintain security, speed, and compatibility in your finished theme.
3. Accessibility
Underscores is designed to make your site usable for everyone, including those who use assistive technologies. Accessible HTML and ARIA roles are part of the theme foundation.
4. Robust Documentation and Community
While Underscores itself is lean, you can find numerous guides, tutorials, and conversations around it. The open-source nature also means you can explore how others are building their themes.
Challenges When Using Underscores
While Underscores is fantastic, it’s good to know its potential drawbacks:
- Not for Beginners: If you’re completely new to HTML, CSS, or PHP, the lack of visual options means a steeper learning curve.
- No Visual Page Builder: It is built for code-first development, not drag-and-drop design.
- Requires Maintenance: As with any custom code, you are responsible for keeping your theme updated.
- No Built-in Design: You start from scratch visually, which adds flexibility but also requires more work.
Practical Tips and Best Practices
To make the most of Underscores, here are some actionable recommendations:
1. Use Version Control
Manage your theme with Git. This helps you track changes and work effectively in a team.
2. Modularize Your Code
Break features into files. Use the /inc directory for custom functions and /template-parts for repeatable templates.
3. Embrace Child Themes for Major Changes
If you later need to build on an existing Underscores-based theme, consider making a child theme to safely add features or styling.
4. Test in Multiple Environments
Check your theme on various browsers and devices to ensure consistency and identify issues early.
5. Follow WordPress Coding Standards
This ensures your theme is compatible with plugins and other WordPress features, and it makes your code easier for others to understand.
6. Keep Accessibility in Mind
Avoid removing accessibility features unless you’re sure what you’re doing. Test with screen readers and contrast checkers.
Cost Considerations
Underscores is open-source and 100% free. There are no licensing fees to use it for your personal or commercial projects.
However, consider these potential costs:
- Hosting and Domain: You’ll need web hosting and a domain for your WordPress site.
- Development Time: Building a custom theme takes time or the investment in a developer.
- Extra Features: Some advanced features (like premium sliders or plugins) may require paid add-ons.
- Shipping Physical Goods: If you’re developing an ecommerce theme, factor in plugins, shipping modules, and payment integrations which may have extra costs.
Real-World Uses for Underscores
Underscores isn’t just for hobbyists. Countless professional themes at major WordPress marketplaces and many custom client sites began as Underscores projects. Agencies use it to quickly create custom, branded experiences without unnecessary fluff.
Frequently Asked Questions (FAQs)
What is the Underscores theme used for?
Underscores is a starter theme for WordPress development. It provides a clean and minimal foundation for building custom themes, helping you get started quickly while following best practices.
Is Underscores a theme or a framework?
Underscores is a starter theme, not a framework. It gives you base files and structure, but not advanced features or tools like theme frameworks. Its minimal approach gives you total control.
Can beginners use Underscores?
While Underscores is clean and organized, it is code-focused. Beginners with some knowledge of HTML, CSS, and basic PHP will get the most out of it. Total beginners may want to start with more visual theme builders first.
Can I sell themes built with Underscores?
Yes! You can use Underscores to create commercial themes. Its open-source license allows both free and premium theme distribution.
How do I keep my Underscores-based theme up to date?
When WordPress standards change, you’ll need to manually update your custom theme. Because you own your code, you decide when and how to update. Regularly check for new best practices and adjust as needed.
Summary
Underscores (_s) is the preferred foundation for coding custom WordPress themes. Its straightforward approach, strong community, and up-to-date best practices make it ideal for developers seeking full design control. If you’re ready to engage with code and want your theme built right from the start, Underscores is your best friend.
By following the steps and tips above, you can streamline your workflow, deliver better results, and keep your WordPress projects modern and robust. Embrace Underscores to make your next theme a professional success!