flag-icons-rails provides flag-icon-css - a collection of all country flags in SVG - as a Ruby gem for use with the asset pipeline.

Add this to your Gemfile:

gem 'flag-icons-rails'

and then execute:

bundle install

Do not add gem to assets section if you want to use flag_icon rails helper.

In your application.css, include the file:

/*
 *= require flag-icon
 */

If you prefer SCSS, add this to your application.scss file:

@import "flag-icon";

Then restart your webserver if it was previously running.

In your view:

<span class="flag-icon flag-icon-by"></span>

<span class="flag-icon flag-icon-by flag-icon-squared"></span>

In your view:

flag_icon(:by)
# => <span class="flag-icon flag-icon-by"></span>

flag_icon(:by, element: :div)
# => <div class="flag-icon flag-icon-by"></div>

flag_icon(:by, squared: true)
# => <span class="flag-icon flag-icon-by flag-icon-squared"></span>

flag_icon(:by, id: 'my-flag', class: 'strong')
# => <span id="my-flag" class="flag-icon flag-icon-by strong"></span>

• lipis for amazing collection of all country flags flags-icon-css
• cfiorini for flag-icon-sass gem this one is based on