Unit Conversions for Cooking & Baking - Complete Kitchen Reference

US vs Metric Measuring Systems in Recipes

One of the most common frustrations home cooks face is encountering a recipe written in an unfamiliar measurement system. The United States primarily uses customary units — cups, tablespoons, teaspoons, and fluid ounces — while most of the rest of the world measures ingredients in grams, milliliters, and liters. Understanding how to move between these two systems is the single most valuable skill you can develop in the kitchen. Whether you are following a French pastry recipe or sharing your grandmother's cookie recipe with a friend overseas, accurate conversions make the difference between success and failure.

Cups to Milliliters: The Essential Conversion

The US customary cup equals 237 mL (often rounded to 240 mL for convenience). This is the starting point for most kitchen conversions. Half a cup is approximately 118 mL, and a quarter cup is about 59 mL. When precision matters — particularly in baking — using a cooking converter tool eliminates guesswork and ensures your measurements are spot on.

Tablespoons and Teaspoons

Smaller volume measurements are just as important, especially for seasonings, leavening agents, and extracts. The standard US tablespoon holds 15 mL, and a teaspoon holds 5 mL. There are exactly 3 teaspoons in 1 tablespoon, and 16 tablespoons in 1 cup. Keep in mind that measuring spoons labeled “tablespoon” can vary by country — the Australian tablespoon, for instance, measures 20 mL, a full one-third larger than the US version. If you are following an Australian recipe, this difference can noticeably affect the outcome, particularly with ingredients like baking powder or salt.

Ounces to Grams: Why Weight Matters in Baking

Professional bakers almost universally measure by weight rather than volume, and for good reason. A cup of flour can weigh anywhere from 120 g to 160 g depending on how it is scooped, sifted, or settled. By contrast, 150 g of flour is always 150 g. The basic conversion is 1 ounce = 28.35 grams. Use our weight converter to switch between ounces and grams instantly.

Common Ingredient Weights (per 1 US cup)

• All-purpose flour: 125 g (4.4 oz)
• Granulated sugar: 200 g (7.1 oz)
• Brown sugar (packed): 220 g (7.75 oz)
• Butter: 227 g (8 oz) — 2 sticks
• Milk: 245 g (8.6 oz)
• Honey: 340 g (12 oz)
• Rolled oats: 90 g (3.2 oz)

Oven Temperature Conversions

Oven temperatures are another area where regional differences cause confusion. American recipes use Fahrenheit, European recipes use Celsius, and some British recipes still reference gas marks. Use our temperature converter for exact values, or refer to these common benchmarks:

• 250 °F = 120 °C = Gas Mark 1/2 (very slow oven)
• 325 °F = 165 °C = Gas Mark 3 (slow/moderate)
• 350 °F = 175 °C = Gas Mark 4 (moderate — most common baking temperature)
• 375 °F = 190 °C = Gas Mark 5 (moderate-hot)
• 400 °F = 200 °C = Gas Mark 6 (hot)
• 425 °F = 220 °C = Gas Mark 7 (hot)
• 450 °F = 230 °C = Gas Mark 8 (very hot)

Scaling Recipes Up and Down

Halving or doubling a recipe sounds simple, but it requires careful attention to unit conversions. When scaling up, multiply every ingredient by the same factor. When scaling down, divide evenly. Weight-based measurements make scaling far easier — halving 300 g is straightforward, while halving “1/3 cup” requires mental gymnastics. For leavening agents like baking soda and baking powder, scale precisely; too much or too little will ruin the texture. Seasonings, on the other hand, are best scaled conservatively and adjusted to taste.

Quick Reference: Common Kitchen Conversions

• 1 US cup = 237 mL (≈ 240 mL)
• 1 US tablespoon = 15 mL
• 1 US teaspoon = 5 mL
• 1 Australian tablespoon = 20 mL
• 1 fluid ounce = 29.57 mL
• 1 ounce (weight) = 28.35 g
• 1 pound = 453.6 g
• 1 stick of butter = 113 g = 1/2 cup = 8 tablespoons
• 1 quart = 946 mL (≈ 1 liter)

With these conversions at your fingertips and a reliable cooking converter, you can confidently tackle any recipe regardless of where it originated. Accurate measurement is the foundation of consistent, delicious results every time you step into the kitchen.