Yeast Converter
Enter the fresh (cake) yeast a recipe calls for and get the equivalent active dry yeast and instant yeast — so you can bake with whatever you have on hand.
Both dry forms at once
Enter the fresh yeast in grams and the calculator returns the active dry yeast (fresh ÷ 2.5) and the instant yeast (fresh ÷ 3) together.
Ratios, not lab values
These are practical kitchen ratios. Brands vary, so treat the result as a reliable starting point rather than a chemically exact figure.
What does the yeast converter do?
From fresh to dry
This yeast converter turns the fresh (cake) yeast a recipe lists into the amount of active dry yeast and instant yeast you would use instead. Fresh yeast is mostly water, so dried forms are far more concentrated and you always need less of them. The two dried forms are not identical: active dry yeast is about 40 percent of the fresh weight (fresh ÷ 2.5), while instant (rapid-rise) yeast is more concentrated still at about one third (fresh ÷ 3). Enter the grams of fresh yeast and you get both equivalents straight away, which is exactly what you need when a recipe assumes one form but your pantry holds another.
Enter the fresh yeast in grams to get the active dry yeast and the instant yeast equivalents instantly.
Active dry yeast is the fresh-yeast weight divided by 2.5, and instant yeast is the fresh-yeast weight divided by 3.
active dry = fresh ÷ 2.5, instant = fresh ÷ 3Because fresh yeast carries so much moisture, the dried forms replace it at a fraction of the weight. Active dry yeast keeps roughly a 2.5-to-1 ratio (about 40 percent), while the more concentrated instant yeast keeps the well-known three-to-one ratio (about 33 percent). Both outputs are returned in grams alongside the fresh amount you entered.
Suppose a recipe calls for 30 g of fresh (cake) yeast.
Divide by 2.5 for active dry
30 ÷ 2.5 = 12 — so you need 12 g of active dry yeast.
Divide by three for instant
30 ÷ 3 = 10 — so you need 10 g of instant yeast.
Pick what you have
Use either 12 g active dry or 10 g instant in place of the 30 g of fresh yeast the recipe lists.
The two outputs tell you how much dried yeast replaces the fresh yeast in your recipe. The ratios are close but not identical: fresh to active dry is roughly 2.5:1 (about 40 percent), while fresh to instant is roughly 3:1 (about 33 percent). That is why 30 g of fresh yeast becomes 12 g of active dry or 10 g of instant — the dried forms are far more concentrated because fresh yeast is largely water, and instant yeast is the more concentrated of the two. Instant yeast has finer granules and can usually be stirred straight into the dry ingredients, while active dry yeast traditionally benefits from being proofed in a little warm liquid first. Whichever you choose, the rise will be comparable to the original recipe; you are simply matching the live-yeast content, not changing the bake.
The conversion is a dependable rule of thumb, but a few practical points are worth keeping in mind.
Approximate ratios that vary by brand
The 2.5:1 (active dry) and 3:1 (instant) ratios are standard approximations — exact strength differs between brands and batches, so use the result as a starting point and adjust to your dough if needed. Active dry yeast should usually be proofed in warm liquid before mixing to confirm it is alive, while instant yeast can go in dry. These figures assume baking yeast, not brewing or wild-yeast cultures.