Finmato
Finmato

Water Intake Calculator

Headaches? Fatigue? Brain fog? You might just be thirsty. Calculate your personalized daily hydration goal to keep your body running at 100%.

lbs
minutes

Daily Goal

87.0 oz

Approx. 11 glasses (8oz each)

*This is a general guideline. Requirements vary based on climate, health conditions, and pregnancy/breastfeeding.

The Essence of Life

Your body is roughly 60% water. It uses fluids to regulate temperature, cushion joints, and transport nutrients. Yet, most of us walk around in a state of chronic mild dehydration, relying on thirst signals that often arrive too late.

Our Water Intake Calculator provides a scientific baseline. Instead of guessing, you get a targeted number in ounces or liters to aim for every day.

How We Calculate It

The basic formula is simple but effective:

Daily Ounces = Body Weight (lbs) / 2

If you weigh 160lbs, your baseline is 80oz. Then, we add roughly 12oz for every 30 minutes of exercise to compensate for sweat loss.

Signs of Dehydration

Don't wait until your mouth is dry. Watch for these subtler signs:

  • Dark Urine: Your goal is pale yellow (like lemonade). Dark yellow (like apple juice) means drink up.
  • Fatigue: A 2% drop in hydration can trigger a noticeable drop in energy and focus.
  • Hunger Pangs: Thirst is often mistaken for hunger. Drink a glass before reaching for a snack.

Athletic Performance

Proper hydration prevents cramps and keeps your heart rate lower during intense exercise.

Skin Health

Well-hydrated skin looks plumper and more radiant. Chronic dehydration can accentuate fine lines.

Kidney Function

Water helps dilute minerals in your urine that can otherwise crystallize into painful kidney stones.

Frequently Asked Questions

Does food count?

Yes! About 20% of your daily water intake comes from food. Fruits like watermelon, cucumbers, and oranges are basically edible water.

Should I drink alkaline water?

For most people, plain tap or filtered water is perfectly fine. Your body is excellent at regulating its own pH levels without expensive specialty waters.

How much is a "cup"?

In the US, 1 cup is 8 fluid ounces (approx 240ml). A standard plastic water bottle is usually 16.9oz (roughly 2 cups).

Medical Consideration

People with heart failure or kidney disease may need to RESTRICT fluid intake. Always follow your doctor's specific advice.

Data Privacy

We do not store your data. This tool runs entirely in your browser.

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