How much water do I add to cut 2 L of 63% spirit down to 40%?
The quick estimate uses conservation of alcohol: the ethanol volume before and after dilution is the same, only the water changes.
Alcohol present: 2.00 L × 0.63 = 1.26 L of pure ethanol.
Final volume needed: 1.26 ÷ 0.40 = 3.15 L.
Water to add: 3.15 − 2.00 = 1.15 L.
Two refinements matter in practice. First, ethanol and water contract on mixing, typically 1 to 3%, so the true water requirement is slightly more than the simple arithmetic suggests; the calculator’s OIML Precise mode handles this. Second, add the water in stages and re-measure with an alcoholmeter at 20°C between additions, because overshooting cannot be undone without stronger spirit.
ABV Dilution Calculator →My sugar wash started at 1.090 and stopped at 1.020 after a week. Stuck or finished?
Stuck. A healthy sugar wash ferments essentially dry, to 1.000 or below, because there are no unfermentable dextrins in plain sucrose. Stopping at 1.020 means roughly a quarter of the sugar is still sitting there unfermented.
The likely cause at 1.090: combined osmotic and alcohol stress on underfed yeast. At 1.020 the wash is already near 9% ABV, and if the nutrients went in as a single dose at pitch, the nitrogen ran out just as the alcohol stress peaked.
The restart sequence that usually works: confirm temperature is in the yeast’s range, add a small nutrient dose, rouse gently to resuspend the yeast without splashing air in, and give it 48 hours. If nothing moves, pitch a rehydrated tolerant strain such as EC-1118, which is the standard restart yeast precisely because it finishes hostile ferments.
Yeast Nutrient Calculator →How much do I throw away as foreshots on a 25 L wash run?
Work from charge alcohol, not from a flat percentage of the collection. A common conservative rule is to discard on the order of 50 mL of foreshots per 10 L of a typical-strength wash charge.
For 25 L of an 8% wash: 25 ÷ 10 × 50 = about 125 mL discarded, and rounding up costs almost nothing.
Two notes on the reasoning. The foreshots discard exists because acetaldehyde and ethyl acetate concentrate at the very front of the run, and those compounds have well-documented unpleasant acute effects. It is not about methanol, which a clean sugar wash barely contains. And the discard is a safety margin, not a precision cut: nothing bad happens if you throw away 200 mL instead of 125, while the reverse is a headache in both senses.
Cuts Calculator →My alcoholmeter reads 84% but the spirit is at 30°C. What is the real strength?
Lower than the display shows. Warm spirit is expanded and less dense, the alcoholmeter sinks deeper, and the scale reads a few points high. The correction therefore goes downward, and the direction trips people up constantly, so here it is done properly.
Alcoholmeters are calibrated at 20°C. At 30°C the reading of 84% corresponds, via the OIML alcoholometric tables, to a true strength of roughly 80.5 to 81% ABV at 20°C: the warm reading overstates the alcohol because the whole liquid expanded, not just the water.
The practical rule: near spirit strength, each degree above 20°C inflates the apparent reading by roughly a third of a percentage point. Ten degrees warm means roughly three points too high. For anything that matters, bottling, dilution arithmetic, records, cool the sample toward 20°C or use the temperature correction tool rather than a rule of thumb.
Temperature Correction Calculator →I have 5 L at 60%. How many 700 mL bottles at 42% will that make?
Alcohol conservation again, in two steps.
Total ethanol: 5.0 × 0.60 = 3.0 L.
Final volume at 42%: 3.0 ÷ 0.42 = 7.14 L.
Bottles: 7.14 ÷ 0.70 = 10 bottles, with about 140 mL left over for the tasting glass.
Contraction shaves the real final volume slightly below 7.14 L, so plan for 10 bottles rather than hoping for 11, and remember the practical losses: racking, filtering and the wet film every vessel keeps all come out of the same budget.
Bottle Yield Calculator →Added water to my gin and it instantly went cloudy. Did I ruin it?
No. That is louching: botanical oils dropping out of solution as the alcohol strength falls. Ethanol was holding those oils dissolved; below roughly 45% ABV, and higher for oil-rich recipes, it no longer can, and the emerging micro-droplets scatter light.
Your options, none of which involve pouring it out: keep the bottling strength a little higher, at or above the point where your recipe stays bright; dilute more slowly next time, resting between additions, which often keeps the same final strength clearer; or chill the diluted gin near 0°C for a day and filter it cold, removing the haze permanently at a small cost in mouthfeel.
Nothing microbial can live at spirit strength, so cloudiness after adding water is chemistry, never spoilage.
Why Spirits Go Cloudy →Is one 5 g packet of EC-1118 enough for 19 L of mead at 1.100?
Lalvin doses EC-1118 at about 25 g/hL, and above 1.060 the rate should scale toward the top of the range because high gravity stresses the yeast.
Baseline: 19 ÷ 100 × 25 = 4.75 g.
Gravity scaling at 1.100: 4.75 × 1.33 = 6.3 g.
So one packet is workable but slightly light for a 1.100 must; a packet and a half removes the doubt. Rehydrate in about 63 mL of clean water at 30 to 35°C for 15 minutes before pitching, and dose nutrients on a staggered schedule, because honey brings almost no nitrogen of its own.
Yeast Pitch Rate Calculator →One calculator says 4 g of Fermaid-O per addition, another says 20 g. Which is right?
Both are doing arithmetic correctly; they disagree about one constant. Fermaid-O contributes about 40 ppm YAN per gram per litre as a raw mass balance, but organic nitrogen is used roughly four times more efficiently than inorganic YAN, which is the basis of the TOSNA protocol. Calculators that ignore the efficiency factor recommend four to five times too much.
Example, 19 L at 13% potential: needed YAN ≈ 234 mg/L.
Raw mass balance: 234 ÷ 40 × 19 = 111 g total. Too much.
TOSNA basis (160 effective): 234 ÷ 160 × 19 = 28 g total, about 7 g per addition at 0, 24, 48 and 72 hours.
The protocol answer lands in the widely quoted 3 to 4.5 g per gallon range. Overdosing is not dangerous, but it wastes nutrient and leaves food for spoilage organisms.
Mead Nutrient Calculator →How much sorbate and Campden to stabilize 23 L of cider before back-sweetening?
Two additions, and both are needed: sorbate stops surviving yeast from multiplying, sulfite keeps bacteria from turning the sorbate into a geranium off-smell. For a typical cider at pH 3.3:
Sorbate: target 200 mg/L sorbic acid; potassium sorbate is 74% sorbic, so 200 ÷ 0.74 × 23 ÷ 1000 = 6.2 g.
Sulfite: free SO2 target = 0.8 × (1 + 103.3 − 1.81) ≈ 25 mg/L; potassium metabisulfite is 57.6% SO2, so 25 × 23 ÷ 0.576 ÷ 1000 = 1.0 g, roughly two Campden tablets.
Confirm fermentation is finished with two identical gravity readings first, rack off the lees, dose both, then wait a day before any sugar goes in. Above pH 3.5 the sorbate target rises to 250 mg/L.
Back-Sweetening Calculator →My mead finished at 0.996. How much honey to sweeten 19 L up to 1.010?
Each gravity point (0.001 SG) needs about 2.6 g of sucrose per litre. Honey is only about 80% sugars by weight, so it takes roughly 3.7 g per litre per point.
Points to add: (1.010 − 0.996) × 1000 = 14 points.
Honey per litre: 14 × 3.7 = 52 g/L.
Total: 52 × 19 = just under 1 kg of honey.
Stabilize first, add the honey in stages, and taste as you go: a high-acid mead carries 1.015 the way a soft one carries 1.008, and honeys vary enough that the factor is an estimate, not a guarantee.
Back-Sweetening Calculator →How much boiling water raises a 6 kg mash in 16 L from 62 to 68°C?
The infusion equation treats the mash as thermal mass: dry grain counts as 0.41 L of water equivalent per kilogram.
Thermal mass: 0.41 × 6 + 16 = 18.5 L equivalent.
With 98°C water: (68 − 62) × 18.5 ÷ (98 − 68) = 3.7 L.
Stir while adding and confirm with a probe: real tuns eat a degree into the vessel walls, so landing half a degree low is normal, and a small top-up corrects it. The new total of about 19.7 L should still fit the tun with headroom before you commit to a mashout step, which takes far more water than people expect.
Mash Infusion Calculator →