How to scale a recipe up or down
Scaling a recipe means keeping every ingredient in the same proportion while changing the total quantity. The key number is the scaling factor, which is your desired servings divided by the original servings:
- Scaling factor = desired servings ÷ original servings
- New amount = original amount × scaling factor
For example, a recipe that serves 4 but needs to feed 6 has a factor of 1.5, so you multiply every ingredient by 1.5. To halve a recipe the factor is 0.5; to double it the factor is 2. The scaler above does this for every ingredient at once — just set your servings or tap a quick-set button.
What does NOT scale linearly
Most ingredients scale cleanly, but a few parts of a recipe need judgement rather than multiplication:
- Cooking time — doubling the batch rarely doubles the time. A larger roast cooks a bit longer; two trays of cookies take about the same as one. Judge by temperature and visual cues, not the factor.
- Pan and pot size — scale the cookware too. Too much batter in one tin won’t bake through; too little spreads thin and burns.
- Seasoning — salt, spices, and strong aromatics often need less than the full multiple. Scale them down slightly and season to taste at the end.
- Eggs — you can’t use 1.5 eggs neatly. Round to a whole egg, or beat an egg and use roughly half by volume for precise bakes.
Scale your saved recipes automatically
This tool is perfect for a one-off resize, but if you cook regularly it gets tedious to re-scale by hand every time. Swoodie stores your recipes and scales them to the number of people you’re feeding in a single tap — then rebuilds your shopping list to match the new amounts automatically. No re-typing, no leftover math.
Pair the scaler with our cooking measurement converter when a scaled amount lands on an awkward unit, or the oven temperature converter if your recipe lists a temperature scale your oven doesn’t use.
Frequently asked questions
How do I halve a recipe?
Multiply every ingredient amount by 0.5. The scaler does this for you when you set the desired servings to half the original, or just tap the ½ quick-set button. Remember that ingredients like eggs don't halve cleanly — see the note on what doesn't scale linearly.
How do I double a recipe?
Multiply every ingredient by 2. Enter your original servings, tap ×2, and the scaler doubles each amount instantly. Watch your pan and pot sizes — doubling the food often means you need a larger dish or you'll need to cook in batches.
How does the scaling factor work?
The factor is simply your desired servings divided by your original servings. A recipe for 4 scaled to 6 has a factor of 1.5, so every ingredient is multiplied by 1.5. This keeps the proportions identical to the original.
Can I scale a recipe to any number of servings?
Yes. Beyond the ½, ×2, and ×3 quick buttons, you can type any desired serving count and the scaler calculates the exact factor. Scaling to 5, 7, or 12 servings works just as well as the round numbers.
Does scaling change the cooking time?
Not proportionally. Doubling a recipe rarely doubles the cooking time — a bigger roast takes somewhat longer, but two trays of cookies take about the same time as one. Use a thermometer or the original visual cues rather than scaling the time by the same factor.
Scaled amounts are exact multiples of what you enter. For very large or very small batches, use your judgement on cooking time, seasoning, and cookware.