Yeast Converter (Fresh, Dry, Instant)

Yeast Conversion Guide

Conversion Ratios

The standard conversions: Fresh yeast to active dry: multiply by 0.4 (or divide by 2.5). Fresh yeast to instant: multiply by 0.33 (or divide by 3). Active dry to instant: multiply by 0.75. So if a recipe calls for 15g fresh yeast: use 6g active dry or 5g instant. If it calls for 7g instant: use approximately 8.75g active dry or 21g fresh. These ratios vary slightly between manufacturers — treat them as close approximations rather than exact conversions.

Active Dry vs Instant Yeast

Active dry yeast requires activation in warm water (35–38°C) for 5–10 minutes before adding to the dough. Instant (fast-action, bread machine) yeast can be added directly to dry ingredients without pre-activation. In terms of leavening power, instant is approximately 25% more active than active dry — hence the conversion factor. Instant yeast also produces a more consistent rise and is less sensitive to water temperature and salt contact. For most home bakers, instant yeast is the most forgiving

Fresh Yeast

Fresh yeast (also called compressed yeast or cake yeast) has a very short shelf life (2–3 weeks refrigerated) but many professional bakers prefer its flavour. It needs to be crumbled and dissolved in warm water or rubbed into flour before use. Fresh yeast is much more difficult to find in UK supermarkets than dried — bakery departments will often sell small blocks directly. It produces a slightly sweeter, more complex fermented flavour, particularly noticeable in enriched doughs (brioche, babka).

Baker's Percentages

Professional bakers express yeast (and other ingredients) as a percentage of total flour weight. Typical yeast levels: yeasted white bread: 1–2% instant (5–10g per 500g flour). Enriched dough (brioche): 2–3% (more yeast needed to overcome fat and sugar). Pizza dough cold-fermented: 0.1–0.3% (very slow fermentation over 24–72 hours develops complex flavour). Sourdough uses no commercial yeast. The lower the yeast percentage, the slower the fermentation and the more complex the flavour development.