Recipe & Baking Calculators
Scale recipes, compare pans, adjust sourdough starter, calculate ingredient costs and plan dough. Includes a conversion chart and printable results.
Start with the task you need to solve. The recipe scaler multiplies an entire ingredient list while keeping its original units. The pan converter finds a batch multiplier from pan shape, count and intended batter depth. Use that multiplier in the scaler to adapt the ingredient amounts.
The three dough tools answer different questions. Baker’s percentages describe an existing formula, including flour and water inside a starter. The starter feeding tool calculates a refreshment by ratio or target mass. The pizza dough planner starts from a required number of dough balls and works backward to ingredient weights.
Weigh ingredients when repeatability matters. Cup-to-gram conversions depend on the ingredient and measuring method; the linked ingredient collections show their weight assumptions. These calculators handle quantities and proportions, not proofing schedules, cooking times or whether a recipe will succeed. Each page includes a reproducible example and explains what its result leaves out.
7 pages in this collection
KEEP THE QUANTITIES CONNECTED
From a different pan to a complete ingredient list
First compare the original and new pans at the intended batter depth. Then send the multiplier to the recipe scaler, enter your ingredient quantities, and print the calculation sheet. Changing pan area changes the amount of batter; it does not tell you a baking time.
Common cake pan conversions
These comparisons use inside dimensions, straight sides and the same batter depth. “1.265625×” means multiply every original ingredient by 1.265625. Values below are rounded to six decimals; the linked tools use full precision.
| Original pan | New pan | Multiply by | Try it |
|---|---|---|---|
| 8-inch round | 9-inch round | 1.265625× | Open comparison: 8-inch round to 9-inch round → |
| 9 × 13-inch rectangle | Two 8-inch rounds | 0.859239× | Open comparison: 9 × 13-inch rectangle to Two 8-inch rounds → |
| 8-inch square | 9-inch round | 0.994020× | Open comparison: 8-inch square to 9-inch round → |
| 9-inch round | 8-inch round | 0.790123× | Open comparison: 9-inch round to 8-inch round → |
Round area is π × radius²; rectangular area is length × width. Multiply each area by its pan count before dividing new area by original area. For example, two 8-inch rounds have 32π square inches of area; a 9 × 13-inch pan has 117. The ratio is about 0.859239, or 85.9239% of the original quantities.
Tapered, tube and Bundt pans need usable-volume information instead. Leave room for rising according to the recipe. See King Arthur Baking’s explanation of pan area comparisons for context.
Choose the calculation you actually need
- Recipe costing works from package quantities and prices to batch and per-serving cost, with optional labor and other expenses.
- Sourdough recipe conversion changes starter amount or hydration while preserving total flour and water. It does not choose a yeast-to-starter equivalent.
- Recipe scaling changes every ingredient by the same serving or batch multiplier. It keeps your unit labels and supports fractional quantities.
- Baker’s percentages describe an existing dough. Starter flour and water are included in the hydration calculation.
- Starter feeding works out retained starter, fresh flour and water. Add your recipe requirement and reserve together when choosing a target mass.
- Pizza dough planning works backward from dough-ball count and weight. Enter the yeast percentage from your recipe; the calculator does not choose a fermentation schedule.
Need to change volume units into weights first? Use the ingredient weight converters and check their grams-per-cup assumptions. Equal cups of different ingredients do not have equal masses.
Updated September 28, 2026. Created with AI and automation; calculations were checked with arithmetic tests, not a kitchen trial or qualified expert review. Reproduce the checks and submit a review.