Recipe scale calculator
Change a recipe from 4 servings to 12 by entering the original and desired serving counts. The calculator scales every ingredient proportionally.
Scaled ingredients
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How scaling works
Scale factor = desired servings ÷ original servings
All ingredient amounts are multiplied by the scale factor. A recipe for 4 that you want to make for 10 has a scale factor of 2.5, so 2 cups of flour becomes 5 cups.
Common scale factors
| Original | Desired | Scale factor |
|---|---|---|
| 4 | 2 | 0.5× (half) |
| 4 | 8 | 2× (double) |
| 4 | 12 | 3× (triple) |
| 6 | 4 | 0.667× |
| 8 | 6 | 0.75× |
Frequently asked
How does the scale factor work?
Scale factor = desired servings ÷ original servings. Every ingredient is multiplied by this factor. A factor of 2 doubles everything; 0.5 halves it.
Can I scale to a fraction of a serving?
Yes — enter decimal servings like 1.5 or 2.5. The calculator handles any positive number.
Why does the scaled amount show a fraction symbol?
The calculator converts decimal amounts like 0.5 to ½ and 0.25 to ¼ for readability. Common baking fractions like ⅓ and ¾ are also recognized.
Does this handle weight and volume units?
The calculator scales the number only — it does not convert between volume and weight. If your recipe uses cups and you want grams, you will need a separate conversion.
How do I share my scaled recipe?
Click "Share with my numbers" to copy a URL that saves your serving counts.