Yeast Conversion Calculator
Convert between fresh, instant, and active dry yeast. Includes amount adjustment when substituting one type for another.
What is a yeast conversion calculator?
The yeast conversion calculator swaps between fresh (cake), active dry, and instant (rapid-rise) yeast. The conversion ratios are well established by professional bakers.
Formula
Fresh = 2.5 × active dry = 3 × instant. So a 7 g packet of instant yeast = 17.5 g active dry / fresh equivalent ÷ 2.5 = 8.75 g active dry.
Worked example
Recipe calls for 21 g fresh yeast. Active dry: 21 / 2.5 = 8.4 g. Instant: 21 / 3 = 7 g.
How to use this calculator
- Enter the amount and unit you have.
- Pick the type you have.
- The equivalent in all three forms appears.
Frequently asked questions
Do I still need to proof active dry yeast?
Yes — dissolve in warm (105–110°F) water with a pinch of sugar for 5–10 minutes before mixing. Skip this for instant yeast (mix directly with flour).
Can I use one for the other?
Yes, with the conversion. Instant and active dry are essentially interchangeable; instant just skips the proofing step. Fresh yeast is harder to find but works in any recipe.
How long does each type last?
Fresh: 2 weeks refrigerated. Active dry / instant: 1 year unopened, 4 months opened in fridge. Old yeast may not rise well — proof a sample first if you're unsure.
Is one better for bread?
All three work for any bread. Fresh gives slightly more flavor; instant is the easiest to use; active dry is most widely available in U.S. supermarkets.