Project
Roulette

Recipe Scaler

Change the serving count and every quantity rewrites itself sensibly.

IntermediateWeb appTool8–16hAI-buildable 4/5no setupworth shipping

Paste a recipe, have the quantities parsed out, and scale it to any number of servings. The parsing is messier than it sounds — fractions, ranges, mixed units — and the output has to stay human, so 0.375 cups should become three eighths, not a decimal.

UI
Logic
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Core features · 7

  • Paste a recipe as free text
  • Quantities and units are detected in the ingredient list
  • A serving control scales every quantity
  • Scaled amounts render as readable fractions rather than decimals
  • Unit conversion between metric and imperial
  • Quantities the parser couldn't read are flagged rather than silently dropped
  • Recipes are saved for later

The interesting part

  • Parsing quantities written as fractions, ranges and mixed numbers
  • Converting decimals back to the fractions cooks actually use
  • Ingredients that don't scale linearly, like leavening and salt

Once it works

  • Add a shopping list combining several recipes
  • Add a cook mode with step timers
  • Scale by a target ingredient amount instead of servings

Suggested stack

reacttypescripttailwindlocalstorage

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