You should reduce the recipe by 20% if using an 8x8 pan instead of 9x9.

I sure wouldn't bother doing that.....you will have about a 4 by 4 square more with the 9 by 9....than the 8 by 8....so figure it's the batter that would have gone into that 4 inch square spread out over all the 8 by 8 pan....not really a noticeable difference....unless the pan is brim full....but you may need to bake it a little longer.

I agree with Lars. OR, place 20% of the crust and filling into a small tart dish/pan and make one 8x8" pan and one tart (which will bake quicker, so keep an eye on it). You can figure the 20% amount by weighing them on a kitchen scale, multiply the weight by 20% and subtracting that amount from the total. Or just eyeball it if you don't have a scale.

But....as my dear departed mother in law would say..."you'll never know the difference from the back of a galloping horse.

Thanks all for the help. I decided it's easier to just buy another pan. I do use the 8x8x2 for other things.

I always use an 8x8 instead of a 9x9 because I don't own a 9x9. Just bake a little longer.

Steve, as a person who doesn't like to shop, I'm amazed that you think it's easier to go buy another pan. lol! FWIW, I have recipes that were written for a 9x9 pan (e.g., brownies and cornbread) that I prefer to bake in an 8x8 because they're too thin/dry otherwise. Some recipes, e.g., quiche-like dishes, might be too thick/wet and not set properly in an 8x8, so it helps to make the decision if you're familiar with the recipe and what it produces in a 9x9.

Cake mixes used to weigh 18.25 oz. Now they weigh 15.25 oz (16% less) but the recommended pan sizes in the instructions hasn't changed. The cakes just come out shorter than they used to.

Hah, good point, Cilantro.

I have been known to fudge on the size of a loaf pan for bread, and it doesn't seem to matter much as far as I know. I'd have to do a side by side test, I guess, one with the recommended size, and one with the size I happen to have, to see and taste the difference. But, I figure, as someone else pointed out, it depends on what you're making.

Sally

Depends on the recipe. If it would fill the 9 x 9, no. The volume of the 8 x 8 is only 79% of the volume of the 9 x 9. Thus the advice to take out 20%.

Thanks all for your input. I used the 8x8 after all (didn't buy another one after all party_music 50) and they came out as well as in the 9x9. Took a little longer to bake is all.

Hope you all have a Merry Christmas and Happy New Year.

I'm glad to know that they came out fine, my advice was going to be to go ahead and use the 8x8 and just bake a bit longer, so it's good to know they came out well.

Annie

Absolutely!....don't sweat the small stuff.....cooking is not a chemical experiment.
Glad it turned out....but I knew it would!