About this tool
Yeast Converter is a free, in-browser tool that converts a yeast amount between the three common forms: active dry, instant (rapid-rise) and fresh (cake) yeast. Enter grams of the type you have and it gives the equivalent weights of the other two, with those highlighted. It all runs in your browser and uploads nothing.
The conversion uses active dry yeast as the base. Instant yeast is more concentrated, so you need about 75% as much (instant = active × 0.75); fresh yeast is much weaker and moister, so you need about 2.5 times as much (fresh = active × 2.5). Your input is first converted to the active-dry equivalent, then out to instant and fresh, keeping all three consistent.
Use it when a recipe calls for one form and you have another. Instant yeast can be stirred straight into the flour, while active dry is often proofed in warm liquid first and fresh yeast is crumbled in — the conversion handles the amount, and you adjust the method.