BakeSpan / About the tool
Useful math. Visible limits.
BakeSpan is a browser-based arithmetic tool, not a recipe testing service or a food safety authority.
Pan conversion
For straight-sided pans with equal batter depth, the multiplier is total new base area divided by total original base area. Round pans use π × radius²; rectangles use width × length. Each area is multiplied by its number of pans. An inch is converted to centimeters using the exact factor 2.54.
Tapered, irregular, and Bundt pans are unsupported. Different batter depths and capacity-based conversions are not implemented. A calculation says nothing about safe fill height or the time needed to bake.
Recipe scaling
The multiplier is new yield divided by original yield, with strictly positive yields using the same definition. Ingredients are multiplied by that factor without rounding the factor first. Ingredient units are retained. Density conversion, nutrition estimates, and hydration calculations are outside this release.
Precision and display
Core decimal quantities use reduced rational numbers backed by JavaScript BigInt. For round-to-round ratios, π cancels. For mixed shapes, the model uses a fixed 40-decimal-place approximation of π. It is a numerical approximation, not a claim of infinitely exact geometry.
The result multiplier is displayed with up to four decimal places and the detail with up to twelve. Ingredient displays use up to two places; CSV values use up to eight. JSON preserves original input strings so the project can be recalculated. Hovering a result exposes the calculated rational fraction. A unit switch converts dimension fields with up to eight displayed decimal places; review measurements after repeated conversions.
Worked checks
| Case | Multiplier | 400 g becomes |
|---|---|---|
| 8 → 10 inch round | 1.5625 | 625 g |
| 8×8 → 9×13 inch rectangle | 1.828125 | 731.25 g |
| 20 → 25 cm round | 1.5625 | 625 g |
| Recipe yield 4 → 10 | 2.5 | 1,000 g |
What this beta has not established
No independent baker or measurement expert has reviewed this release. Human usability testing, screen-reader testing, print-device testing, field performance, and production security review are not complete. The site does not claim professional certification or guaranteed baking outcomes.
Sources and implementation
The explanatory sources below inform the scope and cautions. Their recipe texts, measurement tables, images, and brand assets are not reproduced. The interface illustrations and worked arithmetic examples were created for this site.
- King Arthur Baking: The essential alternative baking pan sizes
- Sally’s Baking: Cake Pan Sizes & Conversions
Core and project schema: version 1.0.0 / schema 1. The owner should keep release notes when changing formulas or data formats.