Health · Hydration check
Water Intake Gauge
Get a daily hydration estimate based on your weight, activity level, and climate — with an honest note about what the number cannot account for.
Instant result
Plain-English why
Copyable takeaway
What this means
This tool estimates daily water needs using 33ml per kg body weight as a baseline, then adjusts for activity, climate, and life stage. Thirst and pale yellow urine are better real-time guides.
Formula used
Base: weight (kg) × 33ml. Adjustments for activity (+350–1,500ml), climate (+0–1,000ml), pregnancy (+300ml), and breastfeeding (+700ml).
Worked example
70 kg, moderately active, temperate climate: 70 × 33 = 2,310ml base + 700ml activity = 3,010ml (~3L, 12 glasses).
Common questions
Does coffee or tea count towards hydration?
Moderate amounts of caffeinated drinks do count, despite the mild diuretic effect. The net hydration benefit is positive at normal consumption levels. Very high caffeine intake may slightly increase fluid needs.
Why does body weight affect hydration needs?
Larger bodies have more metabolically active tissue and a greater total blood volume, both of which increase daily fluid turnover. The standard estimate of 33ml per kg of body weight is a widely used population-level starting point.
Plain-English summary
Enter your weight and activity level to get an estimated daily hydration target.
This section translates the result into a short, direct takeaway rather than leaving the page at a bare number.
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