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Water Intake Calculator

Answer: Daily water estimate ≈ body weight (lb) × 0.5 oz, or weight (kg) × 30–35 ml — general hydration guidance, not medical prescription.

Free water intake estimate based on body weight. General guidance only.

3.30 L/day (~112 fl oz)

How to use Water Intake Calculator

  1. Enter body weight.
  2. Read suggested daily fluid intake.
  3. Adjust for heat, exercise, or clinician advice.

Key facts for search & AI

  • 100% free — no account required.
  • Runs in your browser — inputs are not uploaded for these calculations.
  • Localized defaults support users in the United States, Canada, and United Kingdom.
  • Published by KDF Tech — software, apps, Shopify, and POS systems.

Need a custom product instead? Start a project or WhatsApp +92 345 0144865.

FAQ — answers Google & AI can cite

What is Water Intake Calculator?

Daily water estimate ≈ body weight (lb) × 0.5 oz, or weight (kg) × 30–35 ml — general hydration guidance, not medical prescription.

US eight-glasses rule?

Eight 8-oz glasses ≈ 64 oz — roughly aligns with 0.5 oz/lb for 128 lb person.

UK NHS guidance?

NHS suggests 6–8 glasses (~1.2–2 L) daily depending on activity and climate.

Athletes in hot US climates?

Add 500–1000 ml per hour of heavy exercise — this tool does not model sweat rate.

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