Recipe Scaling Calculator

Recipe Scaling Guide

What Scales and What Does Not

Most ingredients scale linearly with portion size — if doubling a recipe, use double everything. However, leavening agents (baking powder, yeast, bicarbonate of soda) should not be doubled exactly when doubling a recipe — use 1.5× rather than 2×, or the result may be over-aerated and collapse. Salt and spices should be adjusted conservatively to taste — add 75% of the scaled amount first, then season. Strong flavours (chilli, garlic, vanilla, spices) tend to scale non-linearly — less is needed p

Cooking Time Adjustments

Scaling a recipe does not proportionally change cooking time. Doubling a recipe does not mean doubling the time. If doubling, expect approximately 20–30% longer cooking time for roasts and baked goods — but check internal temperature, not time. For stovetop cooking, the extra volume takes longer to come to temperature but simmers at the same rate once hot. Individual portions (muffins, cookies) cook in the same time regardless of how many you make — what changes is the number of batches.

Baking Considerations

Baking is the method most sensitive to scaling errors because the chemistry of baking relies on precise ratios. When scaling down significantly (to 1/4 of original), some recipes simply do not work — minimum quantities of yeast, eggs, or butter are needed for proper structure. When scaling up beyond 3× for baked goods, it is often better to make multiple original batches than one very large one. Egg quantities can be tricky — if you need 2.5 eggs, use 2 and add an extra yolk, or 2 eggs plus a ta

Vessel Size Matters

Scaling a recipe requires scaling the cooking vessel accordingly. A doubled cake recipe needs two original-sized tins, not one doubled tin — pan depth affects heat penetration and cooking time dramatically. For stovetop recipes, a wider pan (rather than a deeper one) is usually better for scaling up, as it maintains proper evaporation rates and browning. Batch cooking for meal prep works well for stews, soups, and curries but less well for dishes that require surface contact with a hot pan.