Yeast converter

Converting between active dry, instant, and fresh yeast

Between baking sourdough and the occasional enriched loaf, I keep running into recipes that call for a kind of yeast I don't have on the shelf. One recipe wants fresh cake yeast, another assumes instant, and the packet in my drawer is active dry. Instead of giving up on a recipe over which yeast it names, I made this converter so you can swap one for another and get the amount right. Tell it what you have and what the recipe wants, and it does the conversion.

Here's how the three types relate and how each one actually behaves, because the amount is only half the story.

The conversion ratios

The three common baking yeasts are active dry, instant (also sold as rapid-rise or bread-machine yeast), and fresh (cake) yeast. The rough working ratios I use are:

• Instant to active dry: active dry is a little less concentrated, so use about 25% more active dry than instant. If a recipe wants 1 teaspoon instant, use about 1¼ teaspoons active dry.
• Active dry to instant: going the other way, use about 25% less instant than the active dry called for.
• Fresh to dry: fresh yeast is mostly moisture, so you need much less dry. A common rule is fresh weighs about 3 times the active dry amount. So roughly 30g fresh ≈ 10g active dry, and instant a touch less still.

These are working approximations, not lab numbers. Yeast is forgiving, and a small difference mostly changes how fast the dough rises, not whether it works.

How each yeast behaves (this part matters more than the grams)

The big practical difference is how you add each one to your dough.

• Active dry yeast traditionally gets bloomed first — dissolved in some warm (not hot) liquid from the recipe, often with a pinch of sugar, and left a few minutes until it looks foamy. That foam is your proof the yeast is alive. Most modern active dry can actually be mixed straight in, but blooming is a nice insurance check, especially if your packet has been in the drawer a while.
• Instant / rapid-rise yeast goes straight into the dry ingredients, no blooming needed. The granules are finer and hydrate quickly. This is what I reach for when I want one less step.
• Fresh (cake) yeast is crumbled and dissolved into warm liquid before use. It's perishable and lives in the fridge, so it's less common in home kitchens, but some traditional recipes are written around it.

How much is in a standard yeast packet?

A standard packet of dry yeast is 7 grams, which is about 2¼ teaspoons. That's true for both active dry and instant packets, so when a recipe just says "one packet," that's your number. If you buy yeast in a jar instead of packets, measuring out 2¼ teaspoons gives you the equivalent of one packet. Knowing this saves a lot of squinting at recipes that mix "packets" and "teaspoons" in the same ingredient list.

A few things I keep in mind when swapping yeast

• Watch the liquid temperature. Warm wakes yeast up; hot kills it. Lukewarm to the touch is the goal, not steaming.
• Rise time will shift. Instant tends to rise a bit faster, fresh can be lively too. Judge doneness by how the dough looks and feels, not strictly by the clock.
• Check the date. Old yeast is the usual reason a loaf won't rise. If you're unsure, bloom a little in warm water first and watch for foam.
• One type is fine for almost everything. You don't need all three. Pick the kind you like working with and convert recipes to match it.

If you want bread to put all this yeast to work in, I share what I bake on my recipes page. And if you like these little kitchen helpers, browse my other free tools.