Question 1

Does the '8 glasses a day' rule have scientific backing?

Accepted Answer

The '8×8 rule' (8 glasses of 8oz = ~1.9L) is a rough guideline, not based on rigorous science. Individual needs vary significantly by body weight, activity, and climate. This calculator gives a more personalized estimate.

Question 2

Does coffee count toward daily water intake?

Accepted Answer

Yes — despite the mild diuretic effect of caffeine, coffee and tea do contribute to your daily fluid intake. The diuretic effect is minimal at typical consumption levels (1–3 cups).

Question 3

What are signs of dehydration?

Accepted Answer

Mild: thirst, dark urine, fatigue. Moderate: headache, dizziness, dry mouth. Severe (1–2% body weight loss): impaired cognitive function, reduced exercise performance. Check urine colour — pale yellow is ideal.

Water Intake Calculator

How to use

Frequently asked questions

BMI Calculator

Calorie & TDEE Calculator

Body Fat % Calculator