WP Shop Cart plugin gives you the option to set shipping prices based on product weight. To calculate shipping based on product weight, you will need to enter weights for each individual product that you would like to charge shipping for. Under each product, there is a “Product Weight” section where you can enter the product weight in lbs (pounds).
Once all the weights are entered, then go to Shipping menu. Select “Weight Rate” from shipping methods and enter the weight rate matrix in the table like the example shown below and click save. WP Shop Cart will do all calculations on the cart page based on the total product weight when a customer checks out.
From the above example, anything less than 10 lbs. will not be charged. Anything over 50 lbs will be charged $35 for local and $45 for international delivery.
Note: Check the shipping required yes.