Cooking fish in the oven is an easy and fun activity to do with your family. But, it is important to know how long it will take for fish in the oven to cook. First, check how thick the fish fillets are so you can calculate how much cooking time you need. To do this: Divide the thickness of each fillet by 5 (thickness is measured using a ruler). For example: I want my fillet at 4 cm thickness. So I divide 4 by 5 = 0.8 (This tells me that 0.8=half inch or about 1/2 inch) Using this figure, add 20 minutes to your calculations based on the actual thickness of your filet:
Thick