What Makes The Data Folder Useful In Jekyll Projects

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In Jekyll projects, the data folder is often underused by beginners, yet it holds immense potential for organizing and reusing content across your site. Instead of hardcoding values or duplicating information in multiple places, the data folder allows you to manage structured information in one location. This article explains what the data folder is, how to use it, and why it is such a powerful tool for building maintainable GitHub Pages sites.

What is the data folder in Jekyll

The data folder, usually named _data, is a special directory in Jekyll where you can store structured data files in formats such as YAML, JSON, or CSV. These files allow you to keep reusable information separate from your layouts and content, making it easier to manage and update information sitewide. For instance, instead of hardcoding a team member list in multiple pages, you can store it in a single YAML file and call it wherever needed.

Why should you use the data folder instead of hardcoding

Hardcoding information across multiple templates leads to redundancy and errors. If you want to update a phone number or add a new team member, you would have to manually edit every instance of that information. This is not only time-consuming but also risky, as you might forget some pages.

By centralizing information in the data folder, you can update it once, and it will reflect across all parts of your site that reference it. This improves consistency, saves time, and ensures accuracy.

What file formats are supported in the data folder

The data folder supports multiple file types, giving you flexibility depending on your project:

  • YAML (.yml or .yaml) – The most common format due to readability.
  • JSON (.json) – Useful for structured data and integration with JavaScript.
  • CSV (.csv) – Ideal for tabular data like product lists or spreadsheets.

Jekyll automatically parses these files and makes the content available inside your templates and includes.

How do you access and use data files in templates

Accessing data files is straightforward. Suppose you create a YAML file inside _data/team.yml with the following content:


- name: Alice Johnson
  role: Designer
- name: Mark Lee
  role: Developer

You can access this data in a layout or include using:

{% raw %}{% for member in site.data.team %}
  <p>{{ member.name }} - {{ member.role }}</p>
{% endfor %}{% endraw %}

This loop will generate a list of team members dynamically, ensuring that updates to team.yml reflect across your site automatically.

What are practical examples of using the data folder

The data folder can be applied in many scenarios. Some common use cases include:

  • Team member lists – Display dynamic staff profiles without repeating code.
  • Navigation menus – Centralize navigation links in one data file.
  • Product catalogs – Build structured product lists from YAML or CSV.
  • Site settings – Store variables like contact info or API keys in data files.
  • Glossaries or FAQs – Keep long lists manageable and reusable.

How does the data folder differ from includes

Includes focus on reusable pieces of HTML or Liquid templates, while the data folder stores reusable content or structured information. They often work together: includes define how something looks, and data provides the content. For example, a navigation menu include might pull its links from a YAML file inside the data folder.

What mistakes should beginners avoid with data files

Beginners often misuse the data folder by:

  • Mixing design and data – Data should contain content, not HTML markup.
  • Overcomplicating structures – Keep data simple and easy to maintain.
  • Forgetting file naming consistency – Use clear, descriptive names for data files.
  • Not documenting file purpose – Contributors may not know what each data file does.

What are the best practices for using the data folder

To get the most from the data folder, follow these guidelines:

  • Organize data files by topic (e.g., team.yml, navigation.yml).
  • Use YAML for readability unless another format fits better.
  • Keep content and structure separate by combining data with includes.
  • Document data file structures in your project’s README.

What should you learn after mastering the data folder

Once you are comfortable using the data folder, the next step is exploring Jekyll collections. Collections let you manage groups of related content, such as portfolios or case studies, in a structured way. By combining data files, includes, and collections, you can build highly flexible and scalable GitHub Pages sites without resorting to complex CMS tools.