From BHG
You can use almost any cake recipe to make cupcakes. Generally, any cake recipe that yields two 8- or 9-inch layers will make twenty-four 2 ¾ x 1 ¾ cupcakes.
If you are converting a Bundt or pound cake recipe, just divide the pan’s volume by ½ cup—the amount of batter needed for each cupcake. For instance, a medium-size Bundt pan holds 9 cups of batter, which means you should get 18 cupcakes from that recipe.
Bake cupcakes at the same temperature required for your cake recipe.