🍳 KitchenCalcs — KitchenCalcs

Baking Pan Size Converter

Free · No sign-up · Last reviewed July 2026

Pick the pan the recipe calls for and the pan you actually have. The converter compares base areas and tells you whether the swap is safe as-is, and if not, exactly how much to scale the recipe.

Pan area reference chart

Pan Base area Approx. full capacity*
6-inch round 28 sq in ≈ 4 cups
8-inch round 50 sq in ≈ 7 cups
9-inch round 64 sq in ≈ 9 cups
10-inch round 79 sq in ≈ 11 cups
8 × 8 inch square 64 sq in ≈ 9 cups
9 × 9 inch square 81 sq in ≈ 11 cups
9 × 13 inch rectangle 117 sq in ≈ 16 cups
10 × 15 inch jelly roll 150 sq in ≈ 21 cups
12 × 17 inch half sheet 204 sq in ≈ 28 cups
8½ × 4½ inch loaf 38 sq in ≈ 5 cups
9 × 5 inch loaf 45 sq in ≈ 6 cups
9-inch springform 64 sq in ≈ 9 cups
10-inch Bundt / tube 72 sq in ≈ 10 cups
12-cup standard muffin tin 66 sq in ≈ 9 cups

*Capacity filled to the brim of a standard 2-inch-deep pan (1 cup = 14.4 cubic inches). Fill only half to two-thirds with batter. Bundt and muffin figures are approximations of equivalent capacity.

The three rules of pan substitution

  1. Stay within ±10% of the original area and you can pour and bake with no changes beyond watching the clock.
  2. Bigger pan = thinner layer = shorter bake. Start checking at 75% of the stated time. A toothpick in the center should come out with moist crumbs, not wet batter.
  3. Smaller pan = deeper batter = longer, gentler bake. If the batter would rise above two-thirds of the pan height, bake the excess as cupcakes instead of overfilling.

Need to resize the recipe itself instead of the pan? Use the recipe scaler with the multiplier this tool gives you, and convert volumes to weight with the cups-to-grams table for the most consistent results.

Frequently asked questions

Can I use a 9-inch pan instead of an 8-inch pan?

Yes, but the batter will sit about 28% shallower (a 9-inch round is 64 sq in vs 50 sq in for an 8-inch), so start checking for doneness 5–10 minutes early. To keep the original height, multiply the recipe by 1.28 — about 1¼×.

What can I substitute for a 9×13 pan?

Two 9-inch rounds (128 sq in total) or two 8×8 squares (128 sq in) are the closest common substitutes for a 9×13 (117 sq in) — both run about 9% larger, which is within the safe range. One 9×9 square is only 81 sq in and would overflow.

How full should I fill a cake pan?

Half to two-thirds full is the rule for standard butter cakes. Fuller than that risks overflow as the batter rises; much less and the cake bakes flat and dry at the edges.

Do I need to change the oven temperature for a different pan?

Usually no — change the time, not the temperature. The exception is glass or dark metal pans: drop the oven 25°F because they absorb and hold more heat than shiny aluminum.

How is pan area calculated?

Rectangles are length × width. Rounds are π × radius², so an 8-inch round is 3.14 × 4² ≈ 50 sq in. Comparing base areas works because most cake batters are baked at similar depths.

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