How to Convert html.slim to html.erb ?

In the world of web development, flexibility and adaptability are paramount. As developers, we often encounter scenarios where we need to convert between different markup languages for various reasons. One such common task is converting HTML.slim files to HTML.erb files. HTML.slim is a concise and elegant markup language, while HTML.erb is a more traditional format used in Ruby on Rails applications. In this comprehensive guide, we'll explore the reasons for conversion, the differences between the two formats, and step-by-step instructions on how to convert HTML.slim to HTML.erb seamlessly.

Understanding HTML.slim and HTML.erb:

Before diving into the conversion process, it's essential to understand the differences between HTML.slim and HTML.erb.


HTML.slim is a Ruby-based template language that offers a more concise and readable syntax compared to traditional HTML. It utilizes indentation and minimal syntax to define markup elements, making it easier to write and maintain code. Slim files typically have a `.slim` extension.


HTML.erb, on the other hand, is a combination of HTML and Embedded Ruby (ERb). ERb allows developers to embed Ruby code directly within HTML files, enabling dynamic content generation. ERb files have a `.erb` extension and are commonly used in Ruby on Rails applications.

Reasons for Conversion:

There are several reasons why you might need to convert HTML.slim files to HTML.erb:

  1. Legacy Codebase: If you're working on a project with an existing codebase that uses HTML.erb files, you may need to convert HTML.slim files to maintain consistency across the application.
  2. Compatibility: Some third-party libraries or plugins may only support HTML.erb format, necessitating the conversion of existing HTML.slim files.
  3. Team Preferences: Different teams or developers may have preferences for using HTML.erb over HTML.slim, leading to the need for conversion to accommodate collaborative development.

Step-by-Step Guide to Convert HTML.slim to HTML.erb:

Now that we understand the rationale behind the conversion, let's dive into the step-by-step process:

1. Install Dependencies (if necessary):

If your project doesn't already have the necessary dependencies installed for processing Slim templates, you'll need to install them. This typically involves adding the `slim-rails` gem to your Gemfile and running `bundle install`.

2. Rename Files:

Rename the `.slim` files that you want to convert to `.erb`. This step is straightforward and can be done using a file explorer or command line.

3. Convert Slim Syntax to ERb:
Open each `.erb` file in a text editor or IDE and update the syntax to ERb format. Replace Slim-specific syntax (such as indentation-based structure and shorthand notations) with equivalent ERb syntax. For example:

  • Replace Slim's `div` syntax:
// HTML.slim
  p Hello, World!
  • with ERb's `<div>` syntax:
<!-- HTML.erb -->
<div class="container">
  <p>Hello, World!</p>

4. Handle Dynamic Content:

If the Slim files contain embedded Ruby code or dynamic content, ensure that it's properly converted to ERb syntax. Replace Slim's `#{}` interpolation with `<%= %>` or `<% %>` tags as needed to evaluate Ruby expressions.

5. Verify Compatibility:

After converting the files, ensure that the application functions as expected. Test the converted HTML.erb files thoroughly to identify any syntax errors or functionality issues introduced during the conversion process.


Converting HTML.slim files to HTML.erb is a straightforward process that involves renaming files and updating syntax. By following the step-by-step guide outlined in this article, you can seamlessly transition between these markup languages while maintaining the functionality and integrity of your web application. Whether you're migrating to a new framework, accommodating team preferences, or ensuring compatibility with third-party tools, understanding the conversion process is essential for efficient web development.

In summary, embracing flexibility and adaptability in your development workflow empowers you to navigate the ever-evolving landscape of web technologies with confidence and ease.