Guide
How to Measure Alcohol Content at Home
Learn what hydrometer readings can tell you about fermentation strength, and where common homebrew estimates fall short.
Alcohol & ABV
Dilute 90% Alcohol to 40%
Estimate the water needed to dilute 90% ABV alcohol to 40% ABV. Enter your starting volume to get a tailored dilution estimate and safety notes. Plan a dilution by volume using the conservation relationship between starting strength, target strength, and starting volume. Use compatible ABV values and measure the final blend.
Enter your measurements
Estimate the water needed to bring a measured alcohol solution to a target strength.
Good to know
Frequently asked questions
Can I add exactly the calculated water volume?
Treat the result as an estimate. Ethanol-water mixtures contract, so blend gradually and verify final strength with an appropriate instrument at its calibration temperature.
Can this calculator make alcohol safe to drink?
No. It only estimates dilution. It does not assess source quality, contaminants, legality, or suitability for consumption.
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