Yeast Conversion Calculator
Convert between fresh, active dry and instant yeast.
Please note: Cooking guides only. Times and temperatures vary with oven calibration, altitude, starting temperature and cut. For anything where safety matters — poultry, pork, sous vide, preserving — use a probe thermometer and follow your national food safety guidance rather than a calculated time.
What the Yeast Conversion Calculator does
The three forms of baker’s yeast differ in moisture and concentration, so they are not interchangeable by weight. Instant is the most concentrated, active dry needs about a quarter more, and fresh yeast — mostly water — needs three times as much.
Formula
Instant : Active dry : Fresh = 1 : 1.25 : 3Active dry = Instant × 1.25Fresh = Instant × 3
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Amount you have | g | Yes | Accepts more than 0. |
| Type you have | one of 3 options | Yes | — |
| Flour in the recipe | g | Optional | Optional — shows the percentage of flour. Accepts 0 or more. |
How to use it
- Choose Type you have.
- Enter Amount you have.
- Optionally add Flour in the recipe.
- Select Calculate.
Worked example
A recipe calling for 7 g of instant yeast.
- Amount
- 7 g
- Type
- Instant
7 g instant equals 8.75 g active dry or 21 g fresh yeast.
Frequently asked questions
Can I swap one yeast for another?
Yes, with the ratio applied. The dough may rise at a slightly different rate, so judge by how much it has grown rather than by the clock.
Does active dry yeast still need proofing?
Most modern brands do not, but dissolving it in warm liquid for five minutes is a free test that it is still alive — worth doing if the packet is old.
Method and sources
Method. Conversion between instant, active dry and fresh yeast at the conventional 1 : 1.25 : 3 ratio by weight.
Assumptions
- The yeast is within date and stored properly; the ratio assumes comparable viability.
Limitations
- The ratio is a long-standing convention and manufacturers differ. Where a package states its own conversion, that supersedes this.
- Converting the quantity does not convert the method: active dry is commonly rehydrated first, instant is not, and fresh behaves differently again.
Sources
- The conversion printed on your own yeast packaging — Varies by manufacturer. The authoritative ratio for a specific product, which differs between brands and supersedes the convention used here.