Pan Size Converter

Convert recipe amounts between different baking pan sizes with automatic scaling factors and adjusted bake times.

Results

Visualization

How It Works

Switching pan sizes in baking requires adjusting ingredient amounts and bake time. The scaling factor is based on the ratio of pan areas -- a bigger pan needs more batter, and vice versa.

The Formula

Scaling Factor = Target Pan Area / Original Pan Area. Round: Area = pi x r^2. Square/Rect: Area = length x width.

Variables

  • 8" round — 50.3 sq inches
  • 9" round — 63.6 sq inches
  • 8" square — 64 sq inches (nearly same as 9" round)
  • 9" square — 81 sq inches
  • 9x13 rect — 117 sq inches (about 1.84x a 9" round)
  • 9x5 loaf — 45 sq inches

Example

Converting from a 9" round (63.6 sq in) to a 9x13 rectangle (117 sq in): factor = 117/63.6 = 1.84. Multiply all ingredients by 1.84.

Tips

  • A 9" round and an 8" square have nearly identical areas. They are interchangeable.
  • One 9x13 pan holds about as much as two 9" rounds -- perfect for layer cakes.
  • Fill pans only 1/2 to 2/3 full to allow room for rising.
  • Darker pans absorb more heat. Reduce oven temp by 25F if switching from light to dark.
  • If you do not have the exact pan size, use two smaller pans and reduce bake time.