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Daily water planning

Hydration Calculator

Calculate baseline water intake from body weight, then add evidence-backed adjustments for training load, climate, pregnancy, or lactation. Results convert to litres, cups, bottles, and hourly reminders so you can pace hydration through the day.

Base: weight × 0.033 L Every 30 min exercise → +0.35 L Hot & humid → +1.0 L

Author · Ekta Rawat

Reviewer · Pawan

Your Daily Water Goal

Based on your profile and activity level

Total Water

2.5 L

Includes all adjustments

Equivalent To

Cups (250mL) 10
Your bottles 3.3
Per hour 156 mL

Morning

600 mL

Afternoon

1000 mL

Evening

900 mL

60%
2.5 L

Your daily hydration goal

Input profile

Weight drives baseline water; all other sliders fine-tune the add-ons.

Lifestyle factors

Workout Hydration Strategy

Pre-workout

250 mL

During

150 mL

Post-workout

350 mL

Hourly Hydration Timeline

Personalized Recommendations

How the calculation works

  1. Baseline: National Academies recommend roughly 0.033 L per kilogram for healthy adults; this covers breathing, digestion, and mild perspiration.
  2. Training load: Every 30 minutes of exercise adds 0.35 L (or 0.5 L for intense sessions) based on ACE hydration research.
  3. Climate bump: Warm weather adds 0.5 L and hot/humid adds 1.0 L to offset higher sweat rates.
  4. Life stage: Pregnancy (+0.3 L) and lactation (+0.7 L) match WHO and hydration-for-health guidance.
  5. Reminder pacing: Total intake divides into meals, hourly sips, and bottle refills so cues are easy to follow.

Interpretation & coaching cues

Urine color cross-check

Pale straw to light yellow usually signals adequate hydration. Dark amber + strong odor → increase fluids and sodium by 250–500 mL.

Meal pairing

Pair at least half your intake with meals to leverage sodium and carbohydrate absorption. Keeps fluids in circulation longer.

Workout split

Example 45 min HIIT: 250 mL pre, 150 mL every 15 minutes, 350 mL post. Add electrolytes when sweating through clothes.

FAQ

Does coffee or tea count?

Yes. Most caffeinated drinks are mildly diuretic but still net-positive for hydration. The calculator lists cups in household measures so you can include unsweetened tea or coffee.

What if I follow a low-sodium diet?

Spread intake, sip slowly, and add electrolytes from vegetables, broths, or oral rehydration packets. Low sodium plus rapid chugging can trigger hyponatremia.

Is the plan safe for kidney or heart conditions?

Always follow clinician fluid limits if you have kidney disease, heart failure, or endocrine disorders. Use this calculator only when medically cleared.

References

  1. Hydration for Health – Hydration calculator methodology.
  2. University of Florida – Daily Water Intake Calculator project notes.
  3. MedIndia – Daily water requirement calculator.
  4. Everyday Health – Hydration calculator overview.
  5. UCD Hydration Calculator – Patient education resource.
  6. National Academies – Dietary Reference Intakes for Water.

Author

Ekta Rawat is CalcArena's Yoga & Nutrition Expert with a decade of coaching experience. She blends hydration science with simple rituals—meal-paired fluids, climate adjustments, and mindful sips—so routines stay sustainable.

Reviewed by · Pawan, M.Tech (Data Science)