Select a yeast To group: This yeast equivalents calculator assumes the world's standard practice weight and volume measurements are: active dry yeast = 0.25 ounce per 2-1/2 teaspoons, instant yeast = 1 ounce every 3 tablespoons. If you weigh your own ingredients, use the corresponding weights instead. The amount of yeast you need depends on what type of yeast you are using. For example, if you are making a batch of bread, you will need more than just a little bit of yeast because you want it to produce lots of bubbles when it starts to rise. Of course, you can always add more yeast at a later time if needed. Instant yeast is easy to measure because it usually comes in a 3-ounce package. Active dry yeast is usually sold in packets or jars that contain approximately 23/4 ounces (100 grams) each. The amount of instant yeast you need depends on how much bread you plan to make. For example, if you are making two batches of bread, you will need almost half as much instant yeast as for one loaf. To calculate the amount of instant yeast you need, divide the number of grams by 100 and then multiply by $0.534. So, if the recipe calls for 50 grams of instant yeast, you would pay $271.40 for a three-packet box of yeast.