What is the ratio between yeast types?

The standard conversion ratios are: Fresh ÷ 2.5 = Active Dry, and Fresh ÷ 3 = Instant. So 30g fresh yeast = 12g active dry = 10g instant. Active dry to instant is × 0.75 (or ÷ 1.33).

What is the difference between active dry and instant yeast?

Active dry yeast needs to be dissolved in warm water (around 38°C) before use and takes longer to activate. Instant yeast (also called fast-action or easy-bake) can be mixed directly into the flour and activates faster. Instant yeast is more potent per gram.

How long does yeast last?

Unopened instant yeast sachets last 1-2 years. Once opened, store in an airtight container in the fridge and use within 4 months. Fresh yeast keeps for about 2 weeks in the fridge. You can freeze fresh yeast for up to 3 months.

Can I substitute fresh yeast for dried in sourdough recipes?

Fresh yeast can be used in any recipe calling for dried yeast using the conversion ratios. However, if a recipe is meant for a natural sourdough starter, commercial yeast will give a different flavour profile — faster rise but less complexity.

Is one type of yeast better than another?

Each type has its place. Fresh yeast gives the best flavour and is preferred by professional bakers, but has a short shelf life. Instant yeast is the most convenient as it needs no activation and stores well. Active dry yeast is the middle ground. For home baking, instant yeast is the most practical choice.

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Yeast Conversion Calculator

Convert between fresh yeast, active dry yeast, and instant yeast quantities.

Converting From

Amount

How We Calculate This

Different yeast types have different concentrations of active yeast cells. Fresh yeast contains the most moisture and therefore requires the highest weight. Instant yeast is the most concentrated.

Conversion Ratios

Fresh to Active Dry: ÷ 2.5
Fresh to Instant: ÷ 3
Active Dry to Instant: × 0.75
Instant to Active Dry: × 1.33

Usage Notes

Active dry yeast: dissolve in warm water (38°C) for 5-10 minutes first
Instant yeast: add directly to flour, no activation needed
Fresh yeast: crumble into flour or dissolve in warm liquid

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Last updated: February 2026

All calculations are based on standard ratios and conversions. Results may vary with specific ingredients, equipment, and conditions.