Setting up Shipping Rates with variable product weight and package weight

[-DM]

Currently we have 3 flat rate shipping options, but we would like to convert to shipping rates that are based off of the product weights, package weight, and location. What is the best way about setting everything up, as we have multiple different packaging types we use for products that are different sizes, so we do not really have a "default shipping package" that shopify requires/uses for their calculations. Is there a way to have shipping rates setup for changing package weights that we use to accurately calculate what shipping would cost?