Protein & water intake calculator.
Enter your weight and goal to see an estimated daily protein target and a daily water amount, from the same rules the One Fitness Hub app uses.
These tools are free to use without an account.
Estimated daily water
2,750 mlAbout 93 fl oz, from drinks and food together.
Estimated daily protein
144 g1.8 g per kg of your body weight.
These are rule-of-thumb figures, not a prescription. Fluid needs change with heat, altitude, sweat and the food you eat, and protein is one part of a diet. Do not use them if a doctor has set a fluid or protein limit for you, for example with kidney, liver or heart conditions or in pregnancy. Drinking far more than thirst asks for can be harmful.
Fitness estimates for adults 18 and over, not medical or dietary advice. Results are informational and are not reviewed by a certified personal trainer.
Where the numbers come from
Protein is set per kilogram of body weight by goal: 1.8 g when maintaining, 2.0 g when gaining muscle, and 2.2 g when losing weight or recomposing. When you are losing weight or recomposing toward a lower target weight, the grams are set on that target weight, so a larger body is not given an unrealistic figure. Water is 35 millilitres per kilogram of body weight, rounded to the nearest 250 ml. These are the rules the One Fitness Hub Nutrition tab uses for its protein and water targets.
What to keep in mind
Water counts from every drink and a share comes from food, and heat, altitude, sweat and illness all change what you need, so thirst remains a guide. Protein is one part of an eating pattern; this page does not set a calorie target. If a doctor has told you to limit fluid or protein, for example with kidney, liver or heart conditions or in pregnancy, follow that advice instead of these figures.
Fitness estimates for adults 18 and over, not medical or dietary advice. Results are informational and are not reviewed by a certified personal trainer. Calculations stay in your browser. Typed measurements are not sent or saved.
Common questions.
Is 35 ml per kg right for me?
It is a common rule of thumb and the one the app uses, rounded to the nearest 250 ml. Heat, altitude, sweat and your diet shift real needs, so treat it as a starting point and let thirst and urine colour guide you.
Why is protein based on my target weight when I want to lose weight?
Setting grams on a lower target weight keeps the figure realistic for a larger body. If you leave the target blank, or it is higher than your weight, the tool uses your current body weight.
Does this set a calorie target?
No. It covers water and protein only. For calories and macros, use the calorie calculator or the TDEE and macro calculator.
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