About the Recipe Scaler
Cooking for six when the recipe serves four, or halving a cake for two, means scaling every ingredient by the same factor, and doing it by hand with amounts like 1 1/2 cups and 3/4 teaspoon is where mistakes creep in. This tool reads the amount at the start of each line, including mixed numbers, fractions, the fraction characters ½ and ¾ and ranges such as 1-2, multiplies it by the ratio of servings, and writes it back in a form a cook can read, such as 2¼ or ⅔. Lines without a number, like a pinch of salt, are kept exactly as written.
Updated October 2026
How to use the Recipe Scaler
- 1Paste your ingredients with one per line and the amount first.
- 2Enter how many servings the recipe makes.
- 3Enter how many servings you want.
- 4Read the scaled list and copy it.
- 5Check spices, baking times and pan sizes yourself.
Tips for scaling well
Write down the recipe's number of servings before you start, and check whether it gives a yield by weight or volume. Cooks often scale by weight in baking because it is more accurate than cups. If a recipe uses whole eggs, a scale-down may call for part of an egg; beat one egg and use the right share by weight, about 50 g per egg without the shell.
Ingredients such as yeast, baking powder and salt are usually safe to scale when changing the batch by up to double or half. Beyond that, treat the result as a starting point.
Common scaling traps
- Spices can overpower a dish when doubled, so add gradually.
- Pan size changes the depth of cakes and bakes.
- Liquids may reduce less in a larger pot, so thickening may need more time.
- Eggs are awkward to halve; use the beaten-egg trick.
- Check oven capacity for big batches.
Related kitchen tools
Use the Cooking Converter for cups, spoons, grams and millilitres, the Unit Converter for general conversions, the Temperature Converter for oven settings and the Proportion Calculator for other ratio problems. The Calorie Calculator and Macro Calculator help you plan portions.
Features
- Reads fractions, mixed numbers and ranges
- Writes tidy amounts like 1½ and ¾
- Leaves lines without a number unchanged
- Fixes cup/cups and egg/eggs to match the new amount
- Any scaling factor, up or down
- One-tap copy
- Works offline in your browser
Frequently asked questions
How do I scale a recipe?
Divide the number of servings you want by the number the recipe makes to get a factor, then multiply every ingredient by it. To go from 4 to 6 servings the factor is 1.5, so 2 cups become 3 cups.
Do all ingredients scale evenly?
Most do, but not all. Salt, spices and strong flavours often need less than a straight scale-up. Leavening in baking may need adjusting for large batches, and pan size and cooking time change when you double or halve a recipe.
What happens to cooking time when I double a recipe?
Roasts and bakes in larger pans usually take longer, not twice as long. Stovetop dishes may need a bigger pot but similar time. Check for doneness rather than relying on the clock.
Can the tool read amounts like 1 1/2 or 1½?
Yes. It understands plain numbers, decimals, fractions like 3/4, mixed numbers like 1 1/2, and the fraction characters such as ½, ¾ and ⅓. Results are written with the nearest eighth or third where possible.
What about weights and metric amounts?
They are scaled the same way. 200 g becomes 300 g when you multiply by 1.5. The unit is kept as written, except that common words like cup, egg and clove switch between singular and plural to match the new amount. Convert units separately if you need to.
Why are some lines left as written?
Lines that don't begin with a number, like salt to taste or a pinch of cinnamon, have nothing to multiply, so the tool leaves them alone and tells you how many it skipped.