Decoding the Rails session cookie
Marshal.load(Base64.decode64(CGI.unescape(cookie.split("\n").join).split('--').first))
As found here.
Update: you can dump your session and verify your session signature using:
secret = "your session secret" # from config/initializers/session_store.rb verifier = ActiveSupport::MessageVerifier.new(secret) signed_message = CGI.unescape(cookie.split("\n").join verifier.verify(signed_message)