It is always nice to have a reference for substituting an item if we do not have on hand the suggested pan in a recipe. If you do not have the size of pan a recipe calls for, perhaps this would be of some help:
Bundt pan (10″ approx.) is the same as using 2 – 8″ round pans.
12 cup muffin tin can be used instead with a 8 l/2″ loaf pan OR
9″ round pan OR 8″ x 8″ square pan.
10″ round pan and 9″ x 9″ square pan are the same.
9″ round pan is the same as 2-8″ round pans OR 10″ x 15″ jelly roll pan OR 8″ x 8″ square pan.