Automobile manufacturers run through some tests to know the maximum weight capacity of your tire depending on its size and pressure. Load rating is identified in alphabetical order and can be found on the sidewall of your tire.
You have to look for the Gross Vehicle Weight Rating of your vehicle which can be found in the owner’s manual. Then with the load index of your new tire, multiply it by four to get the maximum load capacity. You should get higher results than GVWR to get correct rating.