On Jan 24, 11:01 am, "Phrogz" <g... / refinery.com> wrote: > On Jan 24, 11:44 am, "John Kopanas" <kopa... / gmail.com> wrote: > > > This way in rails I can go: > > > @summary.job_cost.to_dollars_with_centsEasier:http://api.rubyonrails.com/classes/ActionView/Helpers/NumberHelper.ht... The latest edition of Mastering Regular Expressions suggests the following regex for commafication: /(\d)(?=(\d\d\d)+(?!\d))/$1,/ Haven't tried look ahead in Ruby but I think this may work for you, perhaps with some special handling of the "cents" portion of the amount. Ken