THE NUMBERS, EXPLAINED
How to use this calculator.
One arithmetic refresh with starter:flour:water ratio 1:c:d. Build exactly production demand plus retained starter; no fermentation timing or maturity prediction.
Start with your inputs
Enter production levain demand (g), starter retained after production (g), feed flour parts per starter part, feed water parts per starter part, starter currently available (g). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Production levain demand (g) | 900 |
| Starter retained after production (g) | 100 |
| Feed flour parts per starter part | 2 |
| Feed water parts per starter part | 2 |
| Starter currently available (g) | 250 |
A worked example
With the example inputs above, starter required for refresh (g) is 200. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Starter required for refresh (g) | 200 |
| Flour and water additions (g) | 400, 400 |
| Current starter surplus (g) | 50 |
How this is calculated
Starter required for refresh (g)
Divide total desired refreshed mass by total ratio parts.
Flour and water additions (g)
Multiply required starter mass by the flour and water ratio parts.
Current starter surplus (g)
Subtract required starting starter from available starter; negative means shortage.
Symbols and units
- a
- Production levain demand (g)
- b
- Starter retained after production (g)
- c
- Feed flour parts per starter part
- d
- Feed water parts per starter part
- e
- Starter currently available (g)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
One arithmetic refresh with starter:flour:water ratio 1:c:d. Build exactly production demand plus retained starter; no fermentation timing or maturity prediction.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Starter required for refresh (g); Flour and water additions (g); Current starter surplus (g). The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: One arithmetic refresh with starter:flour:water ratio 1:c:d. Build exactly production demand plus retained starter; no fermentation timing or maturity prediction.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax: Solve proportions and their applications ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
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