Recipe Scaler
Scale a recipe ingredient up or down for a different number of servings.
Results update as you type.
About this calculator
A recipe scaler adjusts an ingredient quantity when you cook for more or fewer people than a recipe was written for. Enter the original amount and how many servings it makes, then the number of servings you want — it multiplies the amount by the ratio of desired to original servings, so halving, doubling or any odd number in between is automatic. It works with any unit (cups, grams, tablespoons, millilitres) because it only scales the number, and it also shows the amount per single serving.
Worked example: a recipe using 2 cups of flour for 4 servings, scaled to 8 servings, has a factor of 8 ÷ 4 = 2×, so you need 2 × 2 = 4 cups, or 0.5 cup per serving. To cook the same recipe for just 3 people the factor is 3 ÷ 4 = 0.75×, giving 1.5 cups.
Home cooks use it to size a dish to the crowd, stretch a favourite recipe, or shrink a big-batch recipe down to a single portion — running each ingredient through it in turn.
Frequently asked questions
How do I halve or double a recipe?
Multiply every ingredient by the same factor: 0.5 to halve, 2 to double. Setting the desired servings to half or twice the original does this automatically — 2 cups for 4 servings becomes 4 cups for 8 servings.
Does scaling work for cooking times too?
No — only ingredient quantities scale linearly. Cooking times, pan sizes and oven temperatures do not double when you double a recipe, so judge those by doneness rather than multiplying them.
Can the recipe scaler scale to any number of servings?
Yes — enter exactly how many servings you want and the factor is desired ÷ original. Going from 4 servings to 6 is a 1.5× factor, from 4 to 10 is 2.5×, and so on. The amount per serving stays the same however you scale.
Do spices and seasonings scale the same way?
The maths scales them linearly, but taste does not always follow. Strong seasonings — salt, chilli, garlic, spices — are best scaled a little conservatively and adjusted to taste, since doubling can make them overpowering. Scale, then taste and correct.
What about ingredients that come in whole units like eggs?
The tool gives the exact scaled figure — 1.5 eggs, for instance. Round to a whole number, or beat an egg and use half, and adjust the liquid slightly to compensate. Baking is sensitive to ratios, so keep the proportions close.
Does it convert between cups and grams?
No — it only scales the quantity up or down; the unit stays whatever you entered. Use a separate weight-to-volume conversion if you also need to switch between cups and grams, since that ratio differs by ingredient.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/cooking-converter/curl
curl "https://calculator.free/api/v1/cooking-converter/?amount=2&from_servings=4&to_servings=8"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/cooking-converter/?" + new URLSearchParams({
"amount": "2",
"from_servings": "4",
"to_servings": "8"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.