Yeast Converter
Recipe calls for fresh yeast and you have instant, or the other way around? Convert between instant, active dry and fresh yeast in grams, teaspoons and packets.
The three kinds of yeast
- Active dry yeast has larger granules with a layer of dormant cells on the outside. It's traditionally dissolved in warm water (about 100–110 °F / 38–43 °C) before mixing, though modern active dry yeast also works mixed straight into the flour.
- Instant yeast (also sold as rapid-rise, quick-rise or bread machine yeast) has finer granules and can go straight in with the dry ingredients. It's a bit more potent by weight than active dry.
- Fresh yeast (cake or compressed yeast) is moist, crumbly and perishable. It keeps about two weeks in the fridge. It's about 70% water, so you need roughly three times as much by weight as instant yeast.
Yeast conversion chart
The ratio used here, by weight, is instant 1 : active dry 1.25 : fresh 3.
| Instant | Active dry | Fresh |
|---|---|---|
| 1 tsp (3.1 g) | 1¼ tsp (3.9 g) | 9 g |
| 1¾ tsp (5.6 g) | 1 packet: 2¼ tsp (7 g) | 17 g (1 small cake) |
| 1 packet: 2¼ tsp (7 g) | 2¾ tsp (8.75 g) | 21 g |
| 1 tbsp (9.3 g) | 3¾ tsp (11.6 g) | 28 g |
| 2 tbsp (18.6 g) | 2½ tbsp (23 g) | 56 g (about 1 large 2 oz cake) |
In practice, many bakers swap instant and active dry yeast 1:1 and simply expect a slightly slower rise with active dry. The 25% adjustment keeps rising times closer to what the recipe describes.
Replacing yeast with sourdough starter
There's no exact conversion, because a starter's strength depends on how recently it was fed. A common starting point is to replace one packet (7 g) of dry yeast with about 100–200 g of active, bubbly starter. With a 100% hydration starter, which is equal weights of flour and water, subtract half the starter's weight from the recipe's flour and half from its water so the dough stays the same. Expect the rise to take two to three times longer. The baker's percentage calculator can check the final hydration for you.
Storing yeast
- Unopened dry yeast keeps until its best-by date in a cool, dry cupboard.
- Once opened, store dry yeast airtight in the fridge (about 4 months) or freezer (about 6 months). It can be used straight from the freezer.
- Not sure if yours is alive? Stir a pinch of sugar and a teaspoon of yeast into ¼ cup warm water. It should foam within about 10 minutes.
Frequently asked questions
How many teaspoons are in a packet of yeast?
2¼ teaspoons, which is ¼ ounce or 7 grams. This is the same for active dry and instant packets.
How much fresh yeast equals a packet of dry yeast?
About 17 g (one 0.6 oz cake) for a packet of active dry yeast, or about 21 g for a packet of instant.
Can I use instant yeast instead of active dry?
Yes. Use about 25% less instant yeast by weight, or the same amount and keep an eye on the rise. There's no need to dissolve it first.