Normal Urine Output Calculator

Regular And Healthy Urine Output Rate

The normal urine output per hour helps to determine if an individual is producing the right amount of urine in a cycle of 24 hours. The range of normal urine output per day is 800 to 2,000 mL (2). Your normal urine output per day can change based on factors like fluid consumption, degree of activity, and overall health. In other words, 0.5 to 1.5 cc/kg/hour is considered as the normal urine output per hour (3).

The normal urine output per kg and normal urine output per hour need to be measured as the amounts of compounds, like protein, uric acid, ammonia, sodium, potassium, nitrogen, urea, creatine, and hormones are directly proportional to the amount of urine output (1). As per research, the normal urine output per hour for adults and children differs (4). The chart below provides an overview:

How To Use The Urine Output Calculator

For calculating the fluid balance and urine output rate in mL/kg/hr, the following variables are considered:

• Fluid intake
• Patient weight
• Total urine output in a specific period.

Generally, a cycle of 24 hours is taken for calculation.

The urine output calculator uses the following equations:

Urine output in mL/kg/hr = Total urine output in mL / (Weight in kg x Hours)

Fluid balance in mL = Fluid intake in mL – Total urine output in mL.

The normal values for total urine output in healthy adults are 800 – 2000 mL. (considering a fluid intake of 2 L and a period of 24 hrs).

Frequency Of Urination In A Day

The normal urine output for adults varies. Usually, most individuals urinate 6 or 7 times in a 24-hour cycle or a day. Urination between 4 to 10 times a day is generally considered healthy. The frequency of urination depends on the quality of life, lifestyle, and liquid intake (5). A few factors that influence this are:

• Fluid intake
• Age
• Medical conditions (such as diabetes and UTI)
• Size of the bladder
• Types of fluids consumed (consumption of alcohol and caffeine can increase urine production)
• Supplements or diabetes medications

A normal person who consumes 64 ounces of fluid in a 24-hour cycle may urinate about 7 times.

Excessive Urination Volume And Causes

Excessive urination syndrome or polyuria is a condition in which a patient urinates more than the normal range. The urine volume is considered to be excessive if it is more than two and a half liters a day (5).

Excessive urination is a common condition, and you may experience it for several days. However, it should not be a continuous practice. If the individual produces abnormal amounts of urine during sleep, it is called nocturnal polyuria or nocturia (5),(6).

Several factors may cause polyuria, including (6):

• A CT scan or any other hospital test in which a dye is injected into the patient’s body.
• Drinking large amounts of liquids.
• Drinking alcohol and caffeine.
• High blood pressure, kidney disorder, or diabetes mellitus.

Similarly, some people may also experience reduced urine output. Check out the next section to understand the reasons behind it.

Overview Of Lesser Urine Output

The medical term for decreased urine output is oliguria. An individual has oliguria if the urinary output is less than 400 mL (13.5 ounces) in a cycle of 24 hours or less than 20 mL per hour. Oliguria is one of the earliest signs of kidney failure (7). The absence of urine is called anuria, and in this condition, a person urinates less than 50 mL a day.

Oliguria can be temporary or seriously permanent. A few causes of oliguria are (7):

• Dehydration
• Infection Or Trauma: These are serious causes as these can lead to shock, which may block blood flow to different organs. Shock is an emergency medical condition that requires immediate attention.
• Urinary Tract Obstruction: If there is any obstruction or blockage in the urinary tract, the urine fails to pass through the urinary tract, kidneys, urethra, and bladder. This blockage may damage the kidneys.

Kidney Failure And Decreased Urine Output

Decreased urine output is one of the symptoms of kidney failure and is not the sole cause.

The kidneys are a pair of organs located in the lower back. These organs filter food and eliminate toxins from the body through urine. In the interim transfer phase, the toxins remain within the bladder. If kidneys cannot filter waste from the blood, it can lead to kidney failure (8).

Factors that may interfere with your kidney health are (8):

• Severe dehydration
• Prolonged medication: Urine is made by filtering out waste products from the blood. Non-steroidal anti-inflammatory medications like ibuprofen or organ transplant medications like tacrolimus reduce blood flow. This results in smaller amounts of urine.
• Exposure to toxic environmental pollutants
• Kidney trauma
• Type 2 diabetes
• Hypertension
• Kidney infections
• Renal vascular disease

When the body cannot remove waste properly and becomes overloaded with toxins, the kidneys fail to perform their normal activities, leading to kidney failure. Hence, checking the urine output rate with the help of the urine output calculator is recommended to ensure you maintain the normal output rate. However, do not rely solely on the calculator and seek medical advice if you notice you are producing less urine than normal.