Water Intake Calculator
Estimate daily water intake using a simple guideline based on body weight and activity. Results are a general reference, not medical advice.
Informational estimate only. Needs vary by climate, diet, health conditions, and exercise. Calculations run locally in your browser (no inputs are stored or sent to a server).
Guideline used: ~35 ml per kg per day, plus a modest activity adjustment. Cups are approximate (1 cup ≈ 240 ml).
How it works
This tool uses a simple guideline based on body weight, then applies a modest adjustment for higher activity. The base estimate is approximately 35 ml per kg of body weight per day.
- Base estimate: weight (kg) × 35 ml
- Activity adjustment: adds a small amount for moderate or high activity
- Cups: shown as an approximation using 1 cup ≈ 240 ml
This is not medical advice. If you have kidney or heart conditions, are pregnant, or have specific medical needs, consult a clinician.
Examples
- 70 kg, low activity → about 2.45 L (≈ 10 cups)
- 70 kg, moderate activity → modestly higher estimate
- 150 lb, low activity → roughly 2.4 L (approx.)
FAQ
- How much water should I drink per day?
Many people use weight-based guidelines, but needs vary widely by climate, activity, diet, and health.
- Is this a medical recommendation?
No. This is an informational estimate based on a rule-of-thumb and does not replace medical advice.
- Does coffee or tea count as water?
Fluids contribute to hydration, but tolerance to caffeine varies. This tool does not model caffeine effects.
- Why show cups?
Cups help quick planning. This page uses 1 cup ≈ 240 ml as an approximation.
- Is my data stored?
No. Calculations run locally in your browser. Inputs are not stored or sent to a server.