Convert between yeast types
Recipes call for fresh (cake) yeast, active dry yeast or instant yeast almost interchangeably — but the amounts are not equal, because dry yeasts are more concentrated than the water-rich fresh block. This converter swaps any amount of one type for the correct weight of another so your bread, pizza or pastry rises as intended.
How it works
It uses the standard baking ratio fresh : active dry : instant = 3 : 1.5 : 1. The tool normalises everything through fresh yeast as the base unit, then converts back out to the target type:
- active dry = fresh × 0.5, and fresh = active dry × 2
- instant = fresh × 1/3, and fresh = instant × 3
- between the dry forms: instant = active dry × 2/3, active dry = instant × 1.5
So whatever pair you pick, the amount in grams is rescaled by these factors and rounded to two decimals.
Example
Your recipe wants 7 g of active dry yeast but you only have instant. Set From = active dry, To = instant, amount = 7. The tool first finds the fresh-equivalent (7 × 2 = 14 g fresh), then scales to instant (14 × 1/3 ≈ 4.67 g instant).
| Fresh | Active dry | Instant |
|---|---|---|
| 30 g | 15 g | 10 g |
| 6 g | 3 g | 2 g |
| 21 g | ~10.5 g | 7 g |
Instant yeast goes straight into the flour; active dry is usually proofed in warm liquid first. The conversion runs entirely in your browser.
Understanding the three yeast types
Fresh yeast (cake yeast)
Fresh yeast is pressed into a moist block containing living yeast cells suspended in water — typically around 70% moisture by weight. It is the most perishable of the three, with a shelf life of a few weeks in the refrigerator. Bakers who use it regularly prize it for a gentle, slightly milky flavour and reliable activity, but it isn’t widely available in all regions. Many professional bakeries still use fresh yeast for consistency.
Active dry yeast
Active dry is fresh yeast that has been dried and granulated, reducing the moisture to around 8%. The drying process kills the outer cells but leaves the interior viable. Most recipes that specify active dry yeast call for proofing it first — dissolving in warm liquid (usually 38–43°C) for 5–10 minutes to wake the surviving cells before combining with the dough. Packets typically contain about 7 g (roughly 2¼ teaspoons).
Instant yeast (rapid-rise / fast-action)
Instant yeast is dried to an even lower moisture level than active dry, and the granules are finer, which means they can be mixed directly into dry flour without pre-proofing. The finer particle size and added ascorbic acid (in many brands) contribute to faster gas production. Instant yeast can be used in place of active dry without proofing; it begins fermenting as soon as liquid is added to the dough.
Why the ratio is 3 : 1.5 : 1
The ratio reflects the relative concentration of active yeast cells in each form. Fresh yeast is roughly 30% solids; active dry and instant have driven off most of the water to reach around 8% and 4–5% moisture respectively. More concentrated means fewer grams are needed to deliver the same cell count. The 3 : 1.5 : 1 rule is a practical approximation — the exact ratio can vary slightly between brands, but it is accurate enough for all standard baking applications.
Tips for the best rise
- If using active dry, always proof in water around 38–40°C. Water above 50°C kills yeast.
- Instant yeast can go directly into the flour bowl but still needs water added eventually — don’t let it sit dry with salt (salt inhibits yeast).
- Fresh yeast crumbles most easily when cold; let it come to room temperature briefly for easier incorporation.
- If your dough isn’t rising, the most common culprit is dead yeast — test it by proofing a small amount before adding it to the whole batch.