SnapCalc

Daily Water Intake Calculator

Calculate your recommended daily water intake based on your weight, activity level, and climate.

Caffeine has mild diuretic effect — add extra water

How to Use

1. Enter your body weight in kilograms. 2. Select your typical activity level — be honest, most people are less active than they think. 3. Choose the climate you live or work in. Air-conditioned offices actually reduce needs slightly. 4. If you're pregnant or breastfeeding, select that option to add recommended extra fluid. 5. Enter how many coffees or teas you have daily — caffeine has a mild diuretic effect requiring a small offset.

Remember: about 20% of daily fluid comes from food (fruit, vegetables, soups), so your actual drinking target is slightly less than the total shown.

Formula

Total water (ml) = (Weight × 35) × Activity multiplier + Climate adder + Pregnancy adder

Frequently Asked Questions

Does coffee or tea count towards my daily water intake?

Partially. Despite the mild diuretic effect of caffeine, studies show that coffee and tea still contribute to net hydration — they are mostly water. However, the diuretic effect means you need slightly more total fluid compared to someone drinking no caffeine. A practical rule: for each cup of coffee or tea, drink an extra glass of water.

What are the signs of dehydration?

Early dehydration signs include dark yellow urine, dry mouth, headache, reduced concentration, and fatigue. Moderate dehydration adds dizziness, rapid heartbeat, and muscle cramps. A simple check: your urine should be pale straw-yellow. Dark amber urine generally means you need more water.

Does sparkling water count the same as still water?

Yes. Sparkling water, soda water, and mineral water all hydrate equally to still water. The carbonation has no meaningful effect on hydration. Plain sparkling water (no added sugar or flavourings) is a good alternative for those who find still water boring.