Before using this rule, please read the WARNING statement in Section 1.
Use the handy calculation tool to the right to find your carbo/insulin ratio based on the 450 Rule by entering your total daily insulin use (TDIU) in the entry box and clicking on SUBMIT or follow the instructions for the graph below to look up your carbo/insulin ratio.
Instructions for using the 450 Rule Graph
Find your total daily insulin use (TDIU) on the horizontal scale at the bottom of the graph. From your TDIU draw a line vertically up until it intersects the red curve. From the intersection point on the curve, draw a line horizontally to the left until it intersects the Carbo/Insulin Ratio scale and note the number. This is your carbohydrate to insulin ratio based on the 450 Rule.