There is a gem for that!
Thanks to Patrick Lenz who wrote bundle_outdated (gem install bundle_outdated).
In your project directory, execute bundle-outdated:
$ bundle-outdated Finding outdated gems.. Newer versions found for: sass-rails (3.2.5 > 3.2.3) coffee-rails (3.2.2 > 3.2.1) uglifier (1.2.4 > 1.0.3) Lock bundle to these versions by putting the following in your Gemfile: gem 'sass-rails', '3.2.5' gem 'coffee-rails', '3.2.2' gem 'uglifier', '1.2.4' You may try to update non-specific dependencies via: $ bundle update sass-rails coffee-rails uglifier Handwaving specifications: sass-rails: ~> 3.2.3 coffee-rails: ~> 3.2.1 uglifier: >= 1.0.3