What it's for
Recipes call for different yeast forms. Instant Dry is the most concentrated; Active Dry needs a bit more by weight; Fresh (cake) yeast needs the most because it contains more water. This calculator converts any amount you have into the other types and units so fermentation strength stays the same.
- Your recipe lists Instant Dry, but you only have Active Dry or Fresh.
- You need teaspoons or tablespoons from a gram amount (or the reverse).
- You want a quick check against a standard fresh ↔ dry yeast chart.
Looking for yeast or starter from proof time and temperature instead? Use the Leavening Calculator. That tool works out yeast or starter from time and temperature; this one only substitutes Instant, Active Dry, and Fresh amounts.
How conversion works
Instant dry is the starting point (1×). Other commercial types follow the PizzaBlab conversion chart, then we turn grams into teaspoons using how much a teaspoon weighs:
| Yeast type | vs Instant | Grams per teaspoon |
|---|---|---|
| Instant Dry | 1.00× | 3.0 g / tsp |
| Active Dry | ≈1.3344× | 3.84 g / tsp |
| Fresh / Cake | 3.2× | Grams only |
These swap rates are not the same as the time-and-temperature yeast amounts — that is the Leavening Calculator. Rules of thumb (Instant → Active ≈ 1.25–1.3×, Instant → Fresh ≈ 3×, Fresh → Instant ≈ ⅓) remain close. Fresh yeast is never listed in teaspoons — its moisture and texture make scooping unreliable.
Quick examples
- 17 g Fresh ≈ 5.3 g Instant ≈ 7.1 g Active Dry
- 10 g Instant ≈ 13.3 g Active Dry ≈ 32 g Fresh
- 1 tsp Instant ≈ 3 g ≈ 4 g Active Dry (~1 tsp)