Hydration Calculator
2.7L
a day
11 glasses
of 250 ml each
The glasses, drawn out
Frequently asked questions
What is worth knowing about drinking enough every day
How much water should I drink a day?
The usual rule is 8 glasses, that is 2 litres a day, but the need shifts a lot with body weight, movement, climate and what you eat. A closer estimate is 30 to 40 ml per kilo of body weight a day, which is what this calculator works from.
How do I tell whether I am drinking enough?
The colour of your urine is the best sign: pale yellow means well hydrated, dark yellow means drink more, completely clear may mean you are overdoing it. Thirst is already mild dehydration, and fruit and vegetables cover up to a fifth of what you need.
Does exercise raise how much I need?
Yes: training loses water through sweat and through breathing. The practical rule is half a litre more for every hour of moderate activity, up to a litre for hard work. Heat raises it further, which is why climate goes into the calculation.
Does my data stay private?
Yes, and not because we promise it: this tool runs entirely inside your browser. What you type or upload never leaves your device, so it never reaches a server of ours and there is nothing we could keep, read or lose. You can check it yourself: open the page, disconnect from the internet, and the tool keeps working.
Do you store what I enter?
No. There is no database behind this tool: we do not store your files, your text or your results. When you close the tab nothing is left — not here with us, because it never arrived, and not anywhere else.
Do you profile me? Are you GDPR compliant?
We do not profile you: there is no account to create, we never ask for your email to use a tool, and we keep no profile of what you do. We are an Italian company and we work under the GDPR and the other European rules, with the privacy notice and the consent request in plain sight. One thing we say in full rather than hiding it behind a slogan: the ads on the page are Google's, and Google may use cookies to personalise them. You decide from the consent banner: if you say no the ads stay, but they are not personalised, and the tool works exactly the same.
If it is free, how do you make money?
From the ads on the page, and that is all. We do not sell your data, there is no hidden paid plan, there is no limit that eventually asks for your card, and you do not have to sign up. The ads pay for the servers and for the time we spend writing the tools: that is how we can keep them open to everyone.