Pan Size Converter — Find Your Recipe Multiplier

How Pan Size Conversion Works

Recipes develop around a specific batter depth. When you change pan size, you need to maintain roughly the same depth so the bake time and texture remain correct. The multiplier is simply the ratio of the two pan areas.

Multiplier = Target pan area ÷ Original pan area

Scale every ingredient in the recipe by this multiplier.

Area Formulas by Shape

Worked Example: 9×13 to Two 9-Inch Rounds

A sheet cake recipe uses a 9×13 pan (117 sq in). You want to make a two-layer cake using 9-inch round pans (63.6 sq in each = 127.2 sq in total).

Multiplier = 127.2 ÷ 117 = 1.09 — the recipe barely needs scaling. Make the full recipe and split evenly between the two pans. The bake time may shorten by 5 minutes since each layer is half the original depth.

Bake Time Adjustments

Area-based scaling adjusts batter quantity but not depth — the key variable for bake time is depth (volume ÷ area). In practice:

• If switching to the same shape but different size: bake time is roughly proportional to depth ratio
• If depth increases significantly (e.g., 9×13 to 8×8): add 10–20 minutes; test with a toothpick
• If depth decreases (e.g., round to sheet pan): subtract 5–15 minutes; check 10 minutes early

Always use an oven thermometer to verify your oven temperature before applying time adjustments. See our oven temperature converter for convection adjustments.

Common Pan Substitutions

See also our articles on 9×13 to 8×8 pan conversion, round to square pan conversion, and adjusting baking time for pan size.