Shipping Calculate plugin

I need to calculate the shipping cost based on the weight and number of packages, but some products are small and are put in the same package, while others that are large have a separate package. So in the same order I can have one or more packages, but if there are more than one package for each of them I need to calculate the price based on weight.

Is there a plugin, and if there is, could you tell me its name, that gives me the possibility to enter the size of the parcels and calculate which one to use according to the products ordered and their size.

Thanks