Brew pre-boil volume target calculator

Calculate required warm post-boil volume and required pre-boil volume with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use required warm post-boil volume and required pre-boil volume to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Target cold transferred volume (L)
20
Measured warm post-boil transfer loss (L)
1
Cold/warm volume ratio
0.96
Measured evaporation (L/hour)
3
Boil duration (hours)
1
Required warm post-boil volume (L)
21.833333
Required pre-boil volume (L)
24.833333

Try another scenario

Target cold transferred volume (L)
22
Measured warm post-boil transfer loss (L)
1
Cold/warm volume ratio
0.96
Measured evaporation (L/hour)
3
Boil duration (hours)
1
Required warm post-boil volume (L)
23.916667
Required pre-boil volume (L)
26.916667
Calculation method

Calculation method

Required warm post-boil volume (L)

Warm post-boil=targetCold/ratio+warmTransferLoss; pre-boil adds evaporationRate×duration.

Required pre-boil volume (L)

Warm post-boil=targetCold/ratio+warmTransferLoss; pre-boil adds evaporationRate×duration.

Symbols and units
a
Target cold transferred volume (L)
b
Measured warm post-boil transfer loss (L)
c
Cold/warm volume ratio
d
Measured evaporation (L/hour)
e
Boil duration (hours)

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • Cold/warm ratio entered from user measurements; no universal shrinkage assumption. Supported limits: All required fields must be finite values of the exact declared type and within displayed bounds. Lists contain1–1000 finite numbers. JSON tables are numeric rectangular rows, at most100 rows and30 columns; individual tools have stricter shape/domain constraints. Cold/warm ratio entered from user measurements; no universal shrinkage assumption.
Are these inputs private?

These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.

Share this page
Share this calculator

Leave unchecked to share the page without your entered values.