Recipe Scaler
Scale any recipe up or down.
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Cooking for six from a recipe written for four? Enter the original and target serving counts, list your ingredients, and this tool recalculates every amount using a simple scaling factor.
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Recipe Scaling — The Quick Answer
Divide the new serving count by the original to get the scaling factor, then multiply every ingredient by it. Going from 4 to 6 servings is a factor of 1.5, so 200 g becomes 300 g.
Shortcut
Scaling factor = new servings ÷ original servings
Common scaling factors
| From | To | Factor |
|---|---|---|
| 4 servings | 2 | × 0.5 |
| 4 servings | 6 | × 1.5 |
| 4 servings | 8 | × 2 |
| 6 servings | 4 | × 0.67 |
| 2 servings | 5 | × 2.5 |
Scaling works perfectly for most ingredients, but baking is more sensitive — leavening agents, salt, and spices often need adjusting by feel rather than strict multiplication.
How It Works
The Formula
One multiplier for everything
Formula
Factor = new servings ÷ original servings New amount = original amount × factor
Variables
Recipe yield
How many servings the original recipe makes — the reference point.
Target yield
How many servings you want to make.
Scaling multiplier
New divided by original. Above 1 scales up, below 1 scales down.
Note: Cook times generally don't scale linearly — a doubled recipe in a deeper dish may need longer, while a thinner spread may need less. Watch the food rather than the clock.
Worked Example: Scaling 4 Servings Up to 6
One factor applied to every ingredient
Divide desired by original servings
6 ÷ 4 = 1.5 scaling factor
Multiply each ingredient by the factor
200 g flour × 1.5 = 300 g
Repeat for every ingredient
2 eggs × 1.5 = 3 eggs; 1 tsp × 1.5 = 1.5 tsp
Reference Guide
| From | To | Factor |
|---|---|---|
| 4 servings | 2 servings | × 0.5 |
| 4 servings | 6 servings | × 1.5 |
| 4 servings | 8 servings | × 2 |
| 6 servings | 4 servings | × 0.67 |
Where Scaling Works and Where It Breaks Down
Savoury cooking vs baking
Stews, sauces, stir-fries, and roasts are forgiving — multiply everything by the factor and adjust seasoning to taste at the end. Straightforward scaling works well.
Best for: Everyday savoury recipes
Baking is chemistry. Leavening agents, salt, and strong spices often need less than a full multiplication — a doubled cake may need only about 1.5× the baking powder. Pan size and depth also change how it bakes, so results can shift.
Best for: Treating baked goods with extra care
A larger batch in a deeper pan takes longer; a thinner spread cooks faster — but not in proportion. Keep the temperature the same, adjust the time, and judge doneness by eye, thermometer, or touch rather than the original clock time.
Best for: Avoiding over- or under-cooked scaled dishes
How Recipe Scaling Works
Scaling a recipe comes down to one number: the scaling factor, found by dividing the servings you want by the servings the recipe makes. Multiply every ingredient by it and you're done — for most savoury cooking this simple arithmetic works perfectly. The exceptions are worth knowing: baking is ratio-dependent chemistry, so leavening, salt, and strong spices don't always scale linearly, and cooking times change with batch size in ways that aren't proportional. This tool rescales a whole ingredient list at once so you don't have to multiply each line by hand and risk an error on the one that matters.
Key Features
💡 Pro Tips
- →Scale strong seasonings (salt, chilli, spices) by a little less than the full factor, then taste and adjust at the end.
- →For baking, be cautious scaling by more than double — leavening and pan geometry can misbehave.
- →For fractional eggs, beat one and measure: a large egg is about 3 tablespoons, so half an egg is roughly 1.5 tablespoons.
- →Keep the oven temperature the same when scaling; change the time and check doneness rather than trusting the original minutes.
Common Mistakes
Scaling baking leavening linearly
Doubling baking powder or soda in full can make a cake rise then collapse. Baked goods often need proportionally less leavening and salt than a straight multiplication suggests.
Assuming cook time scales with quantity
A bigger batch isn't simply 'twice as long'. Depth and pan size change heat penetration, so keep temperature fixed and judge by doneness.
Fully multiplying potent seasonings
Salt and strong spices intensify disproportionately when scaled up. Scale them a touch under the factor and correct to taste.
Research & Citations
Sources and standards referenced for the factual claims on this page
- [1]
McGee, H. (2004). On Food and Cooking: The Science and Lore of the Kitchen. Scribner.
Reference on the chemistry of baking and why it resists linear scaling.
View source
This calculator is a reference tool, not a substitute for professional advice. Verify important health, financial, legal, or safety decisions with a suitably qualified professional.
Last updated: October 7, 2026
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Frequently Asked Questions
How do I scale a recipe?
Divide the number of servings you want by the number the recipe makes, then multiply every ingredient by that factor. Doubling a 4-serving recipe (to 8) means multiplying everything by 2.
How do I halve a recipe?
Multiply every ingredient by 0.5. Enter the original servings and half as many new servings — the calculator does the rest. Note that half an egg is about 2 tablespoons of beaten egg.
Do I scale baking powder and spices the same way?
Not always. Leavening agents, salt, and strong spices often scale less than linearly — a doubled batch may need only 1.5× the baking powder or salt. Start with the scaled amount and adjust.
Does cooking time change when I scale a recipe?
Yes, and not predictably. A larger volume usually needs more time, a thinner layer less. As a rule, keep the temperature the same and adjust the time, checking regularly for doneness.