How this recipe scaler works
Scaling a recipe means keeping every ingredient in the same proportion while changing how much it makes. The key number is the scale factor — the ratio between the servings you want and the servings the recipe was written for. Work it out once and apply it to everything.
The factor is simply desired servings ÷ original servings. Multiply each ingredient amount by that factor and the recipe stays balanced. The tool above parses the leading number on each line — whether it is a decimal like 1.5, a fraction like 1/2, or a mixed number like 1 1/2 — scales it, and rewrites the line while leaving the unit and ingredient name untouched.
| Goal | Scale factor | Example: 200 g flour becomes |
|---|---|---|
| Halve the recipe | ×0.5 | 100 g flour |
| Increase by half | ×1.5 | 300 g flour |
| Double the recipe | ×2 | 400 g flour |
| Triple the recipe | ×3 | 600 g flour |
Reference note: amounts are rounded to two decimals and shown as tidy fractions (such as 1/4, 1/3, 1/2 and 3/4) where they land close to a common kitchen measure. For baking, scaling by weight gives the most reliable results.
Frequently asked questions
- How do I scale a recipe up or down?
- Divide your desired servings by the original servings to get a scale factor, then multiply every ingredient amount by it. Going from 4 servings to 6 gives ×1.5, so each ingredient is multiplied by 1.5.
- How do I double a recipe?
- Doubling is a ×2 factor: multiply every amount by 2. 200 g flour becomes 400 g and 1 tsp salt becomes 2 tsp, while servings go from 4 to 8.
- How do I halve a recipe?
- Halving is a ×0.5 factor: multiply every amount by 0.5, or divide by 2. So 200 g flour becomes 100 g and 1 cup sugar becomes 1/2 cup.
- How do I convert servings?
- Set the original servings the recipe was written for and the number you want. The scale factor is desired ÷ original, and every ingredient is multiplied by it for the new amounts.
- Do cooking times change when scaling?
- Mostly no — oven temperature and baking time stay roughly the same if pan size and food thickness are unchanged. A deeper pan or thicker layer needs more time; a thinner spread needs less.
- How do I scale a recipe by weight?
- Multiply each ingredient's weight by the same scale factor. Weight-based scaling is the most accurate method for baking because it avoids the rounding errors of volume measures like cups.