Scale any recipe up or down and get clean, cookable amounts
Paste an ingredient list straight in. Quantities like 1 1/2,
½ and 2–3 are all understood.
Every quantity is multiplied by wanted servings ÷ original servings.
The arithmetic is trivial; the useful part is what happens next. A recipe scaled
by 0.75 turns "1 tablespoon" into 0.75 tablespoons, which no one can measure — so
it is stepped down into teaspoons and shown as 2¼ tsp instead.
Amounts are snapped to the nearest eighth where they are close enough to be honest, and shown as ordinary fractions. Weights round to the nearest gram below 100 g and to the nearest 5 g above, because no domestic scale justifies more precision than that.
Doubling a cake does not mean doubling the tin or the baking time. A deeper tin cooks more slowly in the middle; two tins of the original size are usually the better answer. Salt and strong spices are worth adding to taste rather than multiplying blindly, and raising agents behave less predictably past double.
Eggs are the other awkward one. Half an egg is not a useful instruction, so beat one and weigh out half — a large egg is about 50 g without the shell.
Halving or doubling a recipe is simple arithmetic until you end up with "0.375 cups". This calculator rescales every ingredient and then converts the result into measures you can actually use — quarter cups, tablespoons, teaspoons — rather than leaving you with a decimal.