Hangover Hydration Calculator
Estimate how much water to drink around a night of alcohol to blunt dehydration, plus a simple electrolyte plan.
How it works
Alongside = drinks × water per drink · Total = alongside + 500 mL morning top-up · Deficit if skipped ≈ drinks × 100 mL
Alcohol suppresses the hormone vasopressin, so you urinate more and can end the night in fluid deficit — a major contributor to hangover symptoms like headache and thirst. Alternating each drink with a glass of water spaces out alcohol and offsets some of that loss, and a top-up on waking helps you catch up. Water alone will not prevent a hangover — the alcohol and its by-products still matter — but staying hydrated eases the dehydration part.
Worked example
For 5 drinks at 240 mL of water each, you would sip 5 × 240 = 1,200 mL alongside, plus a 500 mL morning glass, for 1,700 mL total — about 7 glasses. Skipping water entirely might leave a rough deficit of 5 × 100 = 500 mL.
Frequently asked questions
Does drinking water prevent a hangover?
It helps with the dehydration component but does not neutralise the alcohol or its metabolites. You may feel better with good hydration, yet the only sure prevention is drinking less or not at all.
Should I add electrolytes?
A pinch of salt and some potassium (from foods or an oral rehydration mix) can help if you have lost a lot of fluid, since plain water alone does not replace salts. Foods like broth, bananas or a rehydration sachet are simple options.
Is it possible to drink too much water?
Yes — forcing very large volumes in a short time can dilute blood sodium dangerously. Sip steadily rather than downing litres at once, and let thirst guide you.
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Educational estimate only — not medical advice, diagnosis, or treatment. Individual needs vary; consult a qualified healthcare professional for decisions about hydration, nutrition, medication, or substance use.