Size and Shape: First things first, the size and shape—all good recipes should specify this. In terms of shape, it’s just a matter of style. Brownies are usually baked in square tin, but it doesn’t mean you can’t do it in round ones—you just need to adapt the recipe a bit. In terms of sizes, the 20 centimetres (8 inches) is the most popular diameter for round tins, while either 20 centimetres by 20 centimetres or 23 centimetres by 23 centimetres (9 inches by 9 inches) are generally standard for square ones. When in doubt, go bigger, as it’s easier to make just a bit more batter.Tin Height: Depending on the type of cake you’re making, you may need to consider the height of the tin. Most cake tins are shallow and are known as sandwich tins, as the idea is to have a couple of these sponge cakes that you then layer up. For something like a fruitcake, where there is no layering, you’ll need a taller tin to support it. Standard cake tins are usually about 2 inches tall. Again, if you’re unsure, go bigger—making a recipe in a smaller tin than warranted will likely result in half-baked batter spilling all over your oven.Removal: A loose-bottomed cake tin can make releasing your cake easier after baking, but these can leak if you don’t line them properly. An alternative is the springform tin, where the walls release with a clasp. These are generally a bit more watertight, although you should still line them. They can, however, be more expensive than standard tins.