Recipe Scale Calculator
Scale a recipe's ingredient quantities up or down — from one serving count to another, or by any ratio — with mixed numbers, fractions and unicode fractions (½, ⅓, ⅔…) parsed and re-formatted back into readable cooking fractions.
Input
Servings the original recipe makes.
Servings you want to make. The scale ratio is target ÷ original — enter any two numbers to scale by a custom factor.
Output
Guides
What does this tool do?
Paste an ingredient list, tell it how many servings the recipe currently makes and how many you actually want, and the calculator scales every quantity for you — no mental math, no fumbling with a fraction while your hands are covered in flour. It's built for the messy reality of real recipes: whole numbers ("2 cups flour"), simple fractions ("1/2 tsp salt"), mixed numbers ("1 1/2 cups sugar"), and even unicode fraction characters like ½, ⅓, ⅔ and ¼ pasted straight from a website or cookbook app.
How the scaling works
The scale ratio is simply target servings ÷ original servings. Doubling a 4-serving recipe to 8 servings scales everything by 2×; shrinking a recipe for 6 down to 4 scales by 0.67×. You aren't limited to whole-number serving counts either — enter any two numbers (say, original "1" and target "1.5") to scale by an arbitrary custom factor, like making one-and-a-half batches of cookie dough.
Each line of your ingredient list is parsed for its leading quantity, and everything after it — the unit and ingredient name — is carried through unchanged. So "3 cups bread flour" scaled by 2/3 becomes "2 cups bread flour," with "bread flour" untouched. Lines with no leading quantity at all (a recipe title, "salt to taste," an instruction like "Preheat oven to 350F") are recognized as non-scalable and passed straight through.
Smart fraction rounding
Multiplying "1 1/2 cups" by an awkward ratio like 2/3 doesn't produce a clean number — it produces 1.0, or with other ratios, something like 2.166666... Rather than showing you a long decimal, the Smart fractions rounding mode (the default) rounds the leftover remainder to the nearest common cooking fraction — eighths, sixths, fifths, quarters, thirds, and halves, including combinations like 3/8 and 5/6 — and writes the result as a mixed number such as "2 1/6 cups." If a value doesn't land close to any common fraction, it falls back to a plain 2-decimal number instead of forcing a misleading fraction. Prefer decimals across the board? Switch the Rounding option to "Decimals" for a plain 2-decimal-place result on every line.
How to use it
- Enter the Original Servings the recipe currently makes.
- Enter the Target Servings you want to end up with.
- Paste your ingredient list, one ingredient per line.
- Choose a Rounding style — smart fractions (recommended for cooking) or decimals.
- Copy or download the scaled ingredient list, ready to cook from.
FAQ
Does it convert units too (cups to grams, etc.)? No — this tool only scales quantities; units and ingredient names are left exactly as you typed them. If you need to convert between measurement systems (cups ↔ mL, ounces ↔ grams), use the separate Cooking Measurement Converter tool.
What happens to lines without a quantity, like "Preheat oven to 350°F"? They're detected automatically and copied into the scaled list unchanged — only lines that start with a number, fraction, or mixed number get scaled.
Can I scale by a factor instead of servings, like "make 1.5x the recipe"? Yes — set Original Servings to 1 and Target Servings to your desired multiplier (e.g. 1.5), and every quantity is scaled by that factor directly.
Does it understand unicode fraction characters like ½ or ¾? Yes — common vulgar fraction characters (¼, ½, ¾, ⅓, ⅔, ⅕, ⅙, ⅛ and more) pasted directly from a website or app are recognized the same as typing "1/4" or "3/4".
Privacy
Everything runs instantly in your browser — your recipe is never sent to a server or stored anywhere.