Recipe Scaler

Type the recipe's original servings, type the number you actually want, and every ingredient quantity multiplies by the ratio. If a recipe serves 4 and you need 6, the scale factor is 1.5 and 200g of flour becomes 300g, 2 eggs becomes 3, 1 tsp salt becomes 1.5 tsp. The shortcuts for double (×2) and half (×0.5) cover the most common cases. The tool rounds to sensible numbers (no "2.7 eggs") and keeps fractions readable.

The thing that breaks scaling is non-linear ingredients. Salt, leavening agents and strong spices don't scale linearly past about 1.5x. If you're tripling a cake recipe, don't triple the baking powder; use 2.25x. If you're halving a curry, halve the chilli but don't halve the spices below ¼ tsp - you lose the flavour profile entirely. Scaling works best between 0.5x and 2x; outside that range, treat it as guidance and taste as you go.

Cooking for 30 from a recipe that serves 6? The scale factor is 5. Multiply each ingredient: 500g pasta becomes 2.5kg, 6 chicken breasts become 30, 200ml of stock becomes 1 litre. The tool handles the maths instantly so you can focus on whether your largest pot can hold 5x the original volume (it usually can't). Plan to cook in two or three batches once you cross 4x the original quantity.

Cooking time does NOT scale linearly with quantity. A roast that serves 4 at 1 hour does not need 5 hours for a roast that serves 20. Use the [meat cooking calculator](/meat-cooking-calculator) for the actual cook time at the new weight. Likewise, a cake baked in a bigger tin needs a slightly lower oven temperature and longer time, not 5x the time at the original temperature. The [cake tin converter](/cake-tin-converter) handles tin-size adjustments.

Cooking for 1 from a recipe that serves 4 means dividing by 4. Most home recipes scale down cleanly to a quarter for stews, traybakes and pasta sauces. Where it gets fiddly: 1 egg becomes ¼ of an egg, which isn't a thing. Either beat 1 egg, weigh it (about 50g whole, 30g white, 20g yolk) and use a quarter; freeze the rest in an ice cube tray; or accept the recipe doesn't halve below half a serving and cook the full batch.

Baking is harder to scale down than cooking. A cake recipe scaled to a single ramekin won't cook the same as the full-tin version because the surface-to-volume ratio is different. For mug cakes and individual portions, search for a recipe written at that scale instead of dividing a bigger one. For savoury cooking, scaling down is forgiving: scaled-down stew, curry, soup or chilli all work fine, and leftovers freeze well for the next solo meal.

Pan size, cook time, oven temperature, mixing time, kneading time, proofing time. Those are physical and biological constraints that don't move with ingredient quantity. A doubled bread recipe still proofs for the same time at the same temperature, but it'll fill a bigger tin. A halved cookie batch bakes in the same 12 minutes at 180°C, but you'll only have one tray instead of two.

Salt, garlic, raw onion and chilli are also worth treating with caution. The first ¼ tsp of salt in a soup is doing most of the lifting; the next ¼ tsp is fine-tuning. If you're scaling a soup down by half, halve the salt; if you're scaling up by 4x, only triple it then taste. The [recipe unit converter](/recipe-unit-converter) handles the cross-system conversions when you're scaling an American recipe at the same time.