About this calculator
This Ramadan hydration calculator helps you plan fluid pacing between iftar and suhoor. Choose your own target, or select a reference beverage intake value based on National Academies adult water-intake guidance. The result shows your estimated window length, mL per hour, glass count, and a practical pacing interval.
Use this as an educational planning aid only. It does not diagnose dehydration, replace thirst cues, or decide whether fasting is medically safe. People with kidney disease, heart failure, fluid restriction, pregnancy, diabetes, recurrent dehydration, or heat illness risk should ask a qualified clinician for personalized advice.
Uses National Academies adult beverage intake reference values when a non-custom target is selected, then divides the selected target across the user's non-fasting drinking window. Safety warnings reference CDC/NIOSH hydration pacing guidance.
Source-backed educational planner
Educational estimate; not a diagnosis or treatment plan.
Formula and method
Target beverage mL is selected by the user or from adult reference beverage values: 3,000 mL/day for adult men, 2,200 mL/day for adult women, 2,300 mL/day during pregnancy, and 3,100 mL/day during lactation. Drinking window hours = time from iftar to the selected suhoor stop time, crossing midnight when needed. mL per hour = target beverage mL ÷ drinking window hours. Glasses = target beverage mL ÷ glass size. Pacing interval in minutes = drinking window minutes ÷ total glasses.
Frequently asked questions
How much water should I drink between iftar and suhoor?+
There is no single safe amount for everyone. This calculator either distributes a target you choose or uses published adult beverage-intake reference values, then spreads that amount across your non-fasting window.
Are the reference targets a medical prescription?+
No. National Academies adequate-intake values are population reference values, not individualized prescriptions. Needs vary with body size, climate, sweating, diet, medications, pregnancy, breastfeeding, and medical conditions.
Should I drink all my water at suhoor?+
Usually no. Many people tolerate fluids better when they are spread through the evening. The calculator provides a pacing interval to avoid relying on one large drink before dawn.
Who should not use this as a self-care plan?+
Anyone with kidney disease, heart failure, fluid restriction, diabetes, pregnancy complications, recurrent dehydration, or symptoms such as fainting, confusion, chest pain, or severe weakness should get medical advice.
Do tea, soup, milk, or fruit count toward hydration?+
Many drinks and water-rich foods contribute to total fluid intake. This calculator focuses on a beverage target you can pace between iftar and suhoor, so you can adjust the target if your meals include substantial fluids.