A Scope & Engine based clean and powerful and customizable and sophisticated paginator for Rails 3


  • Clean

Does not globally pollute Array, Hash, Object or AR::Base.

  • Easy to use

Just bundle the gem, then your models are ready to be paginated. No configuration. Don't have to define anything in your models or helpers.

  • Scope based simple API

Everything is method chainable with less “Hasheritis”. You know, that's the Rails 3 way. No special collection class or something for the paginated values but uses a general AR::Relation instance. So, of course you can chain any other conditions before or after the paginator scope.

  • Engine based I18n aware customizable helper

As the whole pagination helper is basically just a collection of links and non-links, Kaminari renders each of them through its own partial template inside the Engine. So, you can easily modify their behaviour or style or whatever by overriding partial templates.

  • Modern

The pagination helper outputs the HTML5 <nav> tag by default. Plus, the helper supports the Rails 3 unobtrusive Ajax.

Rails versions

3.0.x and 3.1


Put this line in your Gemfile:

gem 'kaminari'

Then bundle:

% bundle


Query Basics

  • the :page scope

To fetch the 7th page of the users (per_page = 25 by default)

  • the :per scope

To show a lot more users per each page (change the per_page value)


Note that the :per scope is not directly defined on the models but is just a method defined on the page scope. This is absolutely reasonable because you will never actually use “per_page” without specifying the “page” number.

Configuring default per_page value for each model

  • paginates_per

You can specify default per_page value per each model using the following declarative DSL.

class User < ActiveRecord::Base
  paginates_per 50


  • the page parameter is in params

Typically, your controller code will look like this:

@users = User.order(:name).page params[:page]


  • the same old helper method

Just call the “paginate” helper:

<%= paginate @users %>

This will render several “?page=N” pagination links surrounded by an HTML5 <nav> tag.

Helper Options

  • specifing the “inner window” size (4 by default)

This would output something like … 5 6 7 8 9 … when 7 is the current page.

<%= paginate @users, :window => 2 %>
  • specifing the “outer window” size (1 by default)

This would output something like 1 2 3 4 …(snip)… 17 18 19 20 while having 20 pages in total.

<%= paginate @users, :outer_window => 3 %>
  • outer window can be separetely specified by “left”, “right” (1 by default)

This would output something like 1 …(snip)… 18 19 20 while having 20 pages in total.

<%= paginate @users, :left => 0, :right => 2 %>
  • extra parameters (:params) for the links

This would modify each link's url_option. :controller and :action might be the keys in common.

<%= paginate @users, :params => {:controller => 'foo', :action => 'bar'}
  • Ajax links (crazy simple, but works perfectly!)

This would add data-remote=“true” to all the links inside.

<%= paginate @users, :remote => true %>

I18n and labels

The default labels for 'previous', '…' and 'next' are stored in the I18n yaml inside the engine, and rendered through I18n API. You can switch the label value per I18n.locale for your internationalized application. Keys and the default values are the following. You can override them by adding to a YAML file in your Rails.root/config/locales directory.

      previous: "&laquo; Prev"
      next: "Next &raquo;"
      truncate: "..."

Customizing the pagination helper

Kaminari includes a handy template generator.

  • to edit your paginator

Run the generator first,

% rails g kaminari:views default

then edit the partials in your app's app/views/kaminari/ directory.

  • for Haml users

Haml templates generator is also available by adding “-e haml” option (this would actually be automatically invoked while the default template_engine is set to Haml).

% rails g kaminari:views default -e haml
  • themes

The generator has the ability to fetch several sample template themes from the external repository (github.com/amatsuda/kaminari_themes) in addition to the bundled “default” one, which will help you creating a nice looking paginator.

% rails g kaminari:views THEME

To see the full list of avaliable themes, take a look at the themes repository, or just hit the generator without specifying THEME argument.

% rails g kaminari:views

For more information

Check out Kaminari recipes on the GitHub Wiki for more advanced tips and techniques. github.com/amatsuda/kaminari/wiki/Kaminari-recipes

Questions, Feedbacks

Feel free to message me on Github (amatsuda) or Twitter (@a_matsuda) ☇☇☇ :)

Contributing to Kaminari

  • Fork, fix, then send me a pull request.

Copyright © 2011 Akira Matsuda. See LICENSE.txt for further details.