Recipes call for whichever yeast the author had on hand. Type the amount and type from your recipe and the converter shows the equivalent in the other two, in grams, teaspoons, packets, and ounces, using King Arthur Baking's professional conversion factors and the standard ¼ oz (7 g, 2¼ tsp) packet.
Working in baker's percentages? The pizza dough calculator converts its yeast automatically, and the bread hydration calculator shows yeast as a percentage of flour. For other kitchen measurements, the unit converter covers weights and volumes. Baking a cake instead? The cake pan converter scales a recipe to a different pan, and our guide to baker's percentages, yeast, and cake pans explains the conversion factors behind both tools.
Frequently asked questions
How do I convert active dry yeast to instant yeast?
By weight, use about 0.83 × the active dry amount of instant yeast; going the other way, use 1.2 × the instant amount of active dry. Those figures come from King Arthur Baking’s professional reference, which converts fresh yeast to active dry at × 0.4 and to instant at × 0.33. In practice many home recipes simply swap the two one-for-one — Red Star’s conversion chart, for example, gives one amount for either dry type — and the difference shows up only as a slightly faster rise with instant.
How do I convert fresh (cake) yeast to dry yeast?
Multiply the fresh yeast weight by 0.4 for active dry or by about one-third for instant. A standard 0.6 oz (17 g) cake of fresh yeast replaces one ¼ oz (7 g) packet of dry yeast, and a 42 g European fresh cube equals about 17 g active dry or 14 g instant. Fresh yeast is roughly 70 % water, which is why you need so much more of it. It keeps only about two weeks in the fridge, so dry yeast is often the practical choice.
How much yeast is in a packet?
One packet of dry yeast (active dry or instant) holds ¼ oz, which is 7 grams or 2¼ teaspoons. Three packets are sold in a strip. Recipes that say “1 packet” work with either active dry or instant yeast. If you buy yeast in a jar, measure 2¼ teaspoons per packet the recipe calls for, or weigh 7 g if your scale is precise enough. Store opened jars airtight in the fridge or freezer — dry yeast keeps for months that way — and bring it back toward room temperature before proofing so it wakes up quickly.
Do I need to proof yeast before using it?
Instant yeast can go straight into the flour. Active dry yeast is traditionally dissolved in lukewarm water, about 100–110 °F (38–43 °C), for 5–10 minutes before mixing; if it foams, it is alive. Modern active dry yeast often works mixed in directly too, but proofing is a cheap insurance policy when a jar has been open a while. Fresh yeast is crumbled into the liquid. Very hot water — around 140 °F (60 °C) — kills yeast, so if you have no thermometer, aim for water that feels just warm on your wrist.
Why can’t I convert fresh yeast in teaspoons?
Fresh yeast is a moist, crumbly block, so a teaspoon of it can weigh very different amounts depending on how it is packed. That is why fresh yeast is sold and measured by weight — as 0.6 oz or 2 oz cakes in the US and 42 g cubes in Europe. The converter shows fresh yeast in grams, ounces, and cakes, and shows teaspoons only for the dry yeasts. If your recipe gives fresh yeast by volume anyway, Red Star counts a packed tablespoon as about 0.75 oz (21 g), but weighing is far more reliable.