Yeast conversion calculator
For ordinary home bread baking, modern active dry and instant yeast can start at equal weights. Fresh yeast uses about three times the dry weight. Enter the yeast in your recipe and choose the type you have.
Common yeast substitutions
| Instant or active dry (g) | Fresh (g) |
|---|---|
| 1 | 3 |
| 3 | 9 |
| 7 | 21 |
| 10 | 30 |
The yeast conversion formula
For modern home-baking active dry and instant yeast, use a 1:1 starting substitution [1]. For fresh yeast, use about 3 g fresh for each 1 g dry, rounded from a fresh-to-dry factor of 0.33 [2].
Fresh yeast (g) ≈ dry yeast (g) × 3
Dry yeast (g) ≈ fresh yeast (g) ÷ 3
Example: 7 g instant yeast becomes about 21 g fresh. In reverse, 15 g fresh becomes about 5 g dry. This calculator intentionally does not convert sourdough starter or guarantee a fermentation schedule.
Packets and spoon measures
A common US dry-yeast packet contains 7 g, approximately 2¼ teaspoons [3]. Other sachets can contain different weights. Use the label’s grams for the actual product, especially when the recipe needs a small dose.
| Recipe amount | What to enter |
|---|---|
| One packet labelled 7 g | 7 g |
| Half a packet labelled 7 g | 3.5 g |
| One packet labelled 11 g | 11 g |
| Fresh yeast from a block | The weighed amount, not the size of the block |
Use the instructions for your yeast
Modern active dry can start more slowly than instant. A bread-machine recipe may call for a different adjustment; rapid-rise yeast is designed for its own method [1]. Check the product directions before applying the general rule. Fresh yeast needs refrigeration [3].
Changing the quantity of a complete recipe? Use the servings calculator. For a longer refrigerated pizza workflow, read cold fermentation. Record the yeast type and the rise that worked in your CookBook recipe notes.
Sources
A little more help
Frequently asked questions
Is one sachet always 7 g?
No. Packet sizes differ. Read the printed gram weight and use that in the calculator.
Can this convert sourdough starter into yeast?
No. Starter also adds flour and water, and its activity changes. Use a recipe developed for that leavening method.
Does changing yeast guarantee the same rise time?
No. Yeast product, dose, dough and temperature change the rise. Follow the recipe and judge the dough.
Still have a question? Visit our help centre.
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Referencing these numbers or explanations? Copy this citation and link to the page.
“Yeast conversion calculator”, CookBook Manager. Updated . https://cookbookmanager.com/tools/yeast-converter
Text, tables and data on this page are available under the Creative Commons Attribution 4.0 licence (CC BY 4.0). Credit CookBook Manager and link to this page when you reuse them.
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