Image & Video APIs

Ruby/Rails SDK

Last updated: Jun-25-2025

The Cloudinary Ruby/Rails SDK provides simple, yet comprehensive image and video upload, transformation, optimization, and delivery capabilities through the Cloudinary APIs, that you can implement using code that integrates seamlessly with your existing Ruby or Ruby on Rails application.

How would you like to learn?

Resource Description
Ruby/Rails quick start Get up and running in five minutes with a walk through of installation, configuration, upload, management and transformations.
Cloudinary Ruby/Rails SDK GitHub repo Explore the source code and see the CHANGELOG for details on all new features and fixes from previous versions.
Cloudinary Academy Try the free Introduction to Cloudinary for Ruby Developers online course, where you can learn how to upload, manage, transform and optimize your digital assets.

Install

Cloudinary's Ruby library is available as an open-source Ruby gem.

To install the Cloudinary Ruby gem, run:

If you use Rails, edit your Gemfile, add the following line and run bundle.

Note
Check that you're using a supported version of Ruby and/or Rails.

Configure

Load the Cloudinary Ruby library

Set required configuration parameters

You can set the required configuration parameters, cloud_name, api_key and api_secret in one of a few ways:

Environment variable configuration

To define the CLOUDINARY_URL environment variable:

  1. Copy the API environment variable format from the API Keys page of the Cloudinary Console Settings.
  2. Replace <your_api_key> and <your_api_secret> with your actual values. Your cloud name is already correctly included in the format.

For example:

Notes
  • When writing your own applications, follow your organization's policy on storing secrets and don't expose your API secret.
  • If you use a method that involves writing your environment variable to a file (e.g. dotenv), exclude the file from your version control system, so as not to expose it publicly.
  • You may also want to check out the API Keys and Credentials video tutorial.
  • When using Cloudinary through a PaaS add-on, such as Heroku, the environment variable is automatically defined in your deployment environment.
  • You can always override the global configuration values specified by passing different values in specific Cloudinary calls.
  • If you use more than one global method of setting configuration options, the order of precedence is:
    CLOUDINARY_URL -> cloud_name -> cloudinary.yml/cloudinary.rb

cloudinary.yml file configuration

Configure the required Cloudinary credentials in your .yml file as follows:

Note
If using Rails, place the above in a cloudinary.yml file in the config folder of your Rails project.

initializer file configuration

Configure the required Cloudinary credentials in your initializer file as follows:

Or alternatively

Note
If using Rails, place the above in a file named cloudinary.rb in the /config/initializers folder of your Rails project.

Set additional configuration parameters

In addition to the required configuration parameters, you can define relevant optional configuration parameters as shown in the examples below:

  • Environment variable:

    If you're using the CLOUDINARY_URL environment variable, you can append optional configuration parameters to the environment variable. For example, adding the optional upload_prefix and secure_distribution parameters:

  • cloudinary.yml:

  • initializer file:

    Or

Note
By default, URLs generated with this SDK include an appended SDK-usage query parameter. Cloudinary tracks aggregated data from this parameter to improve future SDK versions. We don't collect any individual data. If needed, you can disable the urlAnalytics configuration option. Learn more.

Use

Once you've installed and configured the Ruby SDK, you can use it for:

  • Uploading files to your product environment: You can upload any files, not only images and videos, set your own naming conventions and overwrite policies, moderate and tag your assets on upload, and much more. See example
  • Transforming and optimizing images and videos: Keeping your original assets intact in your product environment, you can deliver different versions of your media - different sizes, formats, with effects and overlays, customized for your needs. See example
  • Managing assets: Using methods from the Admin and Upload APIs, you can organize your assets, for example, list, rename and delete them, add tags and metadata and use advanced search capabilities. See example

Quick example: File upload

The following Ruby code uploads the dog.mp4 video using the public_id, my_dog. The video overwrites the existing my_dog video if it exists. When the video upload finishes, the specified notification URL receives details about the uploaded media asset.

Learn more about upload

Quick example: Transform and optimize

Take a look at the following transformation code and the image it delivers:

sample transformation

This relatively simple code performs all of the following on the original front_face.jpg image before delivering it:

  • Crop to a 150x150 thumbnail using face-detection gravity to automatically determine the location for the crop
  • Round the corners with a 20 pixel radius
  • Apply a sepia effect
  • Overlay the Cloudinary logo on the southeast corner of the image (with a slight offset). Scale the logo overlay down to a 50 pixel width, with increased brightness and partial transparency (opacity = 60%).
  • Rotate the resulting image (including the overlay) by 10 degrees
  • Convert and deliver the image in PNG format (the originally uploaded image was a JPG)

And here's the URL that's automatically generated and included in an image tag from the above code:

In a similar way, you can transform a video.

Learn more about transformations
  • Read the image and video transformation guides to learn about the different ways to transform your assets.
  • See more examples of image and video transformations using the Cloudinary Ruby/Rails library.
  • See all possible transformations in the Transformation URL API reference.

Quick example: Get details of a single asset

The following example uses the Admin API resource method to return details of the image with public ID cld-sample:

Sample output:

Learn more about managing assets

Rails-specific features

You can use Cloudinary's Ruby gem for any Ruby application. However, this SDK also provides some extra rails-specific functionality for those developing Ruby on Rails applications:

Sample projects

For additional useful code samples and to learn how to integrate Cloudinary with your Rails applications, take a look at our Sample Projects.

  • Basic Ruby sample: Uploading local and remote images to Cloudinary and generating various transformation URLs.
  • Basic Rails sample: Uploading local and remote images in a Rails project while embedding various transformed images in a Rails web view.
  • Rails Photo Album: A fully working web application. It uses CarrierWave to manage images of an album model (database). Performs image uploading both from the server side and directly from the browser using a jQuery plugin.
  • Active Storage sample: Demonstrates the setup for an Active Storage integration.

Related topics

✔️ Feedback sent!

Rate this page: