How much soil to fill Vivosun 5 gallon grow bags?

I am switching from 3 gallon plastic pots to 5 gallon Vivosun grow bags for my next grow.

Does anyone know how much soil does it takes to fill each bag?

I ordered a 5 pack and plan on using a fox farm soil… Any suggestions?

Not 100 percent but I think 1.5 cubic feet of soil covers just over 2- 5 gallon bags… the fox farms I buy comes in 2 cubic foot bags and i can usually fill 3 1/2 ish 5 gallon fabric pots I believe transplanting from 3’s you should get 4- pots outa 2 cubic foot bag somewhere close to those numbers