Gravity dilution and boil-off calculator
Gravity points behave like a solute: dilute the volume and the points fall in proportion.
L/h
Water to add
3.273L
- Or volume to boil away
- 0.000
- Boiling time needed
- 0:00:00
- Final volume
- 21.273
- Total gravity points in the wort
- 1170.0
- Current points
- 65.0
Show the working
- Current volume = 18
- Current gravity = 1.065
- Target gravity = 1.055
- Evaporation rate = 3
- Current points = (1.065 - 1) * 1000 = 65
- target_points = (1.055 - 1) * 1000 = 55
- Total gravity points in the wort = 65 * 18 = 1170
- needed_volume = 55 > 0 ? 1170 / 55 : 0 = 21.2727
- Water to add = max(21.2727 - 18, 0) = 3.272 73
- Or volume to boil away = max(18 - 21.2727, 0) = 0
- Boiling time needed = 3 > 0 ? 0 / 3 * 3600 : 0 = 0
- Final volume = 21.2727 = 21.2727
Values are shown to six significant figures here; the arithmetic itself runs on exact fractions and is only rounded where a number is printed.
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The formula
- gravity points x volume is conserved when you add or remove water