Water Intake Calculator
Quick answer
Get a personalised daily water target based on your body weight and activity level — shown in litres and in regular 250 ml glasses, so it is easy to track through the day.
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How the target is calculated
Base: weight (kg) × 0.033 = litres per day
Moderate training: + 0.5 L · Heavy training: + 1.0 L
Glasses = litres ÷ 0.25 (standard 250 ml glass)
Hot weather, pregnancy and breastfeeding increase needs further — listen to thirst too.
Worked example
- 1
A 68 kg woman: 68 × 0.033 = 2.24 L base.
- 2
She trains moderately: + 0.5 L → 2.74 L/day.
- 3
In glasses: 2.74 ÷ 0.25 ≈ 11 glasses of 250 ml.
Interpreting your hydration
| Your result | Category | What it means |
|---|---|---|
| Pale yellow / clear | Well hydrated | You are likely well hydrated — keep up your current intake. |
| Light to medium yellow | Adequate | Normal everyday hydration for most people. |
| Dark yellow | Needs more fluids | Drink an extra 2–3 glasses today. Persistent dark urine most of the day is a sign to drink more. |
| Very dark or brown | Dehydrated | Drink fluids now and, if it persists or comes with other symptoms, see a healthcare provider. |
Urine colour is the simplest everyday hydration check.
Frequently asked questions
Sources & further reading
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This calculator provides general estimates for informational purposes only and is not medical advice. For personal guidance, consult a qualified healthcare provider.