Total Body Water (TBW) Calculator

This online calculator is used to find the quantity of water present in human body.

Using Total Body Water (TBW) calculator

1. Select your gender.
2. Then, select your Age.
3. Enter your height either in centimeters or in feet and inches.
4. Then, enter your weight either in kilograms or pounds.
5. Choose one of the formulas to calculate. Currently we are providing options to choose Watson Formula or Hume-Weyer Formula.
6. Finally, click the Calculate TBW button. The total body water will be calculated with your chosen formula, and the result will be displayed in the box below the button.

Total Body Water (TBW) is the total amount of water present in the body in the form of body fluids, tissues and organs. In a broad way, water content is a human body is divided into two types; intracellular fluid and extracellular fluid. Intracellular fluid is the water stored inside the cells. It constitutes about two third of the total body water content. Extracellular fluid is the water stored and flowing outside the cells. Extracellular fluid constitutes about one third of the total body water. An average female adult human body contains 50% of water and a male adult body contains 60% of water. But this amount varies based on various factors like height, weight, age, disease, etc...

There are several formulas to calculate the total body water content. The popular and most used ones are the formulas put forward by:

• Watson PE, Watson ID and Batt R called as Watson Formula (TBW-W).
• Hume R, Weyers E called as Hume-Weyer Formula (TBW-H).
• Chertow GM, Lazarus JM, Lew NL, Ma L, Lowrie EG calles as Chertow Formula (TBW-C).

Total Body Weight Formulas

1. Watson Formula

TBW-W (for Male) = 2.447 - (0.09156 x A) + (0.1074 x ht) + (0.3362 x wt) litres

TBW-W (for Female) = -2.097 + (0.1069 x ht) + (0.2466 x wt) litres

Where:

• A = age in years.
• ht = Height in centimeters(cm).
• wt = Weight in kilograms(kg).

2. Hume-Weyer Formula

TBW-H (for Male) = (0.194786 x H) + (0.296785 x W) - 14.012934

TBW-H (for Female) = (0.344547 x H) + (0.183809 x W) - 35.270121

Where:

• H = Height in centimeters(cm).
• W = Weight in kilograms(kg).

3. Chertow Formula

TBW-C = H x (0.0186104 x W + 0.12703384) + W x (0.11262857 x M + 0.00104135 x A - 0.00067247 x W - 0.04012056) - A x (0.03486146 x M + 0.07493713) - M x 1.01767992 + D x 0.57894981

Where:

• A = age in years.
• H = Height in centimeters(cm).
• W = Weight in kilograms(kg).
• M = Male (Yes = 1, No = 0).
• D = Diabetes (Yes = 1, No = 0).

• Total body water volumes for adult males and females estimated from simple anthropometric measurements: Watson PE, Watson ID, Batt R. The American Journal of Clinical Nutrition, Volume 33, Issue 1, 1 January 1980, Pages 27–39.
• Relationship between total body water and surface area in normal and obese subjects: R. Hume and Elspeth Weyers. Journal of Clinical Pathology, April 1, 1971; Volume 24: 234–238.
• Development of a population-specific regression equation to estimate total body water in hemodialysis patients: Glenn M. Chertow, J. Michael Lazarus, Nancy L. Lew, Lihong Ma, Edmund G. Lowrie. Kidney International, May 1997; Volume 51, Issue 5, Pages 1578–1582.