Explore a simple weight-based fluid estimate. This calculator uses a fixed heuristic, not an individual hydration assessment, and should not override medical advice about fluid intake.
How to use this tool
- Choose the weight unit and enter a positive weight.
- Select the activity adjustment.
- Read the displayed estimate together with the formula assumptions.
How to interpret the result
The code starts at 35 ml per kg and adds 0, 200, 400 or 600 ml for the selected activity level. It clamps output to 1,500–4,500 ml. These software limits are not safe intake boundaries; climate, diet, illness and prescribed fluid restrictions are not assessed.
Frequently asked questions
Is the result a required daily amount?
No. Treat it as a rough illustration only. Follow professional advice if your health circumstances require a specific fluid plan.