How to make your URLs pretty with friendly_id in Rails

Replacing record IDs in your URLs with the name of your record is incredibly useful for SEO purposes as well as making the links people share more descriptive and self-explanatory.

It’s also very easy using the friendly_id gem.

What is a slug?

A slug is a unique user friendly record identifier. For example in the URL, john-smith is the slug generated from the user record’s name.


First off we’ll want to install friendly_id. We can do that by running gem install friendly_id or adding gem 'friendly_id' to your Gemfile and running bundle install.

After that we’ll want to run rails generate friendly_id to generate the friendly_id config file and generate the migration for setting up the table.

Note: As of writing if you’re running Rails 5.1+ you’ll have to go into the generated migration and add your rails version to the migration so it looks like this:
~~class CreateFriendlyIdSlugs < ActiveRecord::Migration[5.1]

Then you’ll want to run rake db:migrate.

Adding Friendly ID to your model

From here you just need to add this to your model:

~~extend FriendlyId
~~friendly_id :name, use: :slugged

This will use the name column of your table to generate a slug for your record automatically when your save it.

Note that this won’t update if you update the name column. We will cover how to make that happen later.

Using slugs in your URLs

There are two sides to adding slugs to your URLs. In your views when generating the URL and in your controllers when looking up records.


This is as simple as just using .slug instead of .id when generating your paths. For example:

~~foo_path(id: foo.slug)

Instead of



To look up a record by a slug you’ll want to use Foo.friendly.find(params[:id]) instead of Foo.find(params[:id]. This searches by slug as well as by the id of the record, allowing old URLs to still work.

If you don’t want to use friendly.find and instead want to make find work as if you had you should modify your friendly_id call on your model to look like this:

~~friendly_id :name, use: [:slugged, :finders]


Update slugs on column change

What happens if we have a conflict?

Using a function for the slug

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