When measuring dry ingredients or liquids, 6 teaspoons, or 2 tablespoons, is equal to 1 ounce. This converts to 30 grams when using a metric measurement. While many American cookbooks use volume to measure ingredients, throughout much of the world, weight is more commonly used to measure ingredients for cooking.
Many online tools are available to convert measurements in recipes. While converting from weight to volume is not as exact as using a scale, the exchange is close enough to allow someone to complete a recipe without the use of a scale. Some foods, such as butter, have slightly different conversions due to their weight.