Food
Cake Tin Conversion Calculator
Enter from and to tin sizes (diameter or L×W) and an ingredient weight to scale.
Convert a cake recipe between tin sizes
When a recipe assumes one tin and you own another, scale ingredient weights by the ratio of tin areas. Round tins use πr²; rectangular tins use length × width. You can convert round-to-round, rect-to-rect, or between shapes because area is the common currency. Depth still matters for batter rise and bake time — area scaling does not automatically fix a much shallower tin. Weigh the scaled ingredient and keep chemical leaveers reasonable on very large jumps. For party quantities see cupcake quantity; for dry staple portions see rice portion.
Worked example
20 cm round to 23 cm round: area ratio ≈ (11.5/10)² ≈ 1.32×. A 200 g flour line becomes ~264 g.
Limits and assumptions
Ignores tin depth and dark vs light pans. Very large scale-ups may need adjusted leavening and time — use judgement.
Frequently asked questions
What about bundt and ring tins?
Approximate with the effective batter footprint or weigh a water fill to compare volumes instead.
Do liquids scale the same?
Yes by area/volume assumptions — measure liquids by weight when possible for accuracy.
Can I scale eggs?
Scale the weight of egg used; round to whole eggs and adjust with a splash of liquid if needed.
Square tin from round recipe?
Toggle shapes and enter L×W equivalent — area ratio still applies.