Recipe Scaling Calculator

Scaling a recipe by a factor

To scale a recipe by a factor, take the target/original portion ratio and multiply every ingredient by it. Say a recipe for 4 servings uses 100 g of flour and you want 6 servings: that's a factor of 1.5×, which gives you 150 g of flour. The same multiplication works for sugar, fat, liquid, and eggs. There are two things to watch out for, though. First, seasoning and salt do not scale linearly, so use 1.3× the salt instead of the full factor and tweak it by tasting, because your palate stops registering the difference past a point. Second, cooking time and temperature don't scale linearly either. A bigger batch is denser and soaks up heat more slowly, which often means dropping the temperature and giving it more time. With cakes, doubling means either a pan with twice the area (radius × √2) or splitting the batter across 2 identical pans. Don't just dump extra batter into the same pan — the middle stays raw while the edges go brown.

Applications and context

This is bread and butter in catering, restaurant kitchens, birthday and wedding parties, and weekly meal prep. There's a reason pro kitchens write recipes per 100 g or per portion: it lets them scale fast without rounding errors piling up. Volume measures like cups and spoons drift the more you multiply them, so scale by mass whenever you can.

FAQ

How do I handle fractional eggs? Beat an egg, weigh it (it'll be around 50 g), and pour off the fraction you need. If you'd rather not bother, round to the nearest whole egg and nudge the liquid a little to compensate.

Does baking powder scale linearly? It does up to about 3×. Past that, in really big batches, knock it back by roughly 10%, since too much leavening can make a cake collapse.

Can I scale down by 0.5×? You can, but be careful with anything used in tiny amounts to begin with, like yeast, salt, or baking powder. Below about 1 g they stop behaving reliably, so treat that as a floor.