---
slug: measuring-and-units
title: "Measurement Units and Kitchen Scales"
summary: "How Cook:RE handles US and metric units, kitchen scale preferences, and density-backed conversions."
watches:
  - apple/CookRE/Sources/RecipeApp/PreferencesView.swift
  - apple/CookRE/Sources/RecipeCore/Display
  - lib/recipe-core/src/quantity
---

# Measurement Units and Kitchen Scales

Cooking by volume (cups and tablespoons) and baking by weight (grams and ounces) require different tools. Cook:RE lets you configure how measurements are displayed and uses density-backed conversions so your measurements are reliable and repeatable.

## Measurement Preferences

You can customize your measurement system at any time:

1. Open Cook:RE and tap the gear icon to open **Preferences**.
2. Select **Measuring**.
3. Choose your preferred **Volume** system:
   - **Cups:** US customary volume units (cups, tablespoons, teaspoons, fluid ounces).
   - **Millilitres:** Metric volume units (millilitres, litres).
4. Choose your preferred **Weight** system:
   - **Grams:** Metric mass (grams, kilograms).
   - **Ounces:** US customary mass (ounces, pounds).
5. Toggle **Kitchen Scale**:
   - Turn this on if you use a digital kitchen scale. When enabled, Cook:RE displays a weight alongside the volume measurement whenever the ingredient's physical density is known.

## Density-Backed Conversions

Converting a cup of all-purpose flour to grams is not a simple unit calculation because a cup of flour weighs roughly 120 grams, while a cup of granulated sugar weighs roughly 200 grams, and a cup of water weighs 237 grams.

Each ingredient is linked to a curated substance catalog containing physical density data:
- When an imported recipe lists `2 cups all-purpose flour`, Cook:RE looks up the density of all-purpose flour to display `240 g` if your scale preference is active.
- If a recipe lists grams and your preference is cups, Cook:RE converts grams back to volume using the substance's specific density.

## Kosher Salt Brands

Different brands of kosher salt have drastically different crystal shapes and packing densities:
- **Diamond Crystal:** Fluffy, hollow flakes weighing roughly 2.8 grams per teaspoon.
- **Morton:** Denser, flatter flakes weighing roughly 4.8 grams per teaspoon (nearly twice as salty by volume).

In **Preferences → Measuring**, you can select which kosher salt brand is in your pantry. When you view a recipe calling for kosher salt by volume, Cook:RE automatically adjusts the quantity to match your brand's density, preventing accidentally over-salted or under-salted dishes.