Yeast: conversion, amount and fermentation
Convert fresh, active dry and instant yeast or estimate a practical starting range for your flour weight, fermentation time and temperature.
Advanced options
Used only for packet conversions and the approximate packet count.
PEKI uses time and temperature to estimate a starting range. Judge readiness by dough development, not the clock alone.
Rich dough often ferments more slowly; the calculator does not automatically increase the amount.
How to use the yeast calculator
Conversion uses one shared ratio. The flour mode is a conservative starting model: longer fermentation generally needs less yeast, while cooler conditions slow fermentation. The result is intentionally a range.
Quick yeast answers
How much dry yeast replaces 21 g fresh yeast? About 7 g instant yeast or about 8.4 g active dry yeast using the PEK conversion ratio.
How much yeast for 500 g flour? There is no single correct amount. Enter both time and temperature because they materially change the useful starting range.
Why use less yeast for long fermentation? A smaller inoculation has more time to multiply and produce gas; judge final dough readiness by volume, structure and strength.