How big does a cage need to be for 2 gerbils?

well...a two to three foot cage is recommended for one gerbil and if you two most likely a three foot cage or a four foot cage would be best

to make sure you don't spend to much money ...make sure you have two of the same kind of gerbil..boy and boy ...girl and girl because when gerbils have babies they have alot and then you need a bigger cage or multiple cages. =P