How to Convert Microwave Time to Conventional Oven Time

Locate the traditional cooking time of the food item. For boxed food, this can be found on the side or back of the box. For wrapped foods such as meats, the cooking time is located on a label. If no cooking time can be located on the item's packaging, consult a cookbook.

Set the microwave heat setting to "High." A microwave's highest power setting is the equivalent of a 375-degree conventional oven.

Divide the conventional oven cooking time by four. According to the University of Tennessee Extension Office, microwave cooking required one-fourth the time of conventional oven cooking. For example, if a recipe requires an hour of conventional cooking time, the microwave cooking time would decrease to 15 minutes.