Cardiac Output Calculator




cardiac output equation


Cardiac output

beats/min
milliliters (mL)/beat

0.0 mL per minute



This cardiac output calculator calculates the volume of blood, in milliliters (mL) that will be pumped by the heart in 1 minute.

Cardiac output is a way or test of measuring the health of a person's heart. The volume of blood which a person pumps out each minute tells whether the person has a properly functioning and normal heart or one that is not.

The 2 variables which determine the cardiac output are the person's heart rate and stroke volume.

Heart rate is the number of times in 1 minute that a person's heart beats. It is measured in unit beats/min.

Stroke volume is the volume of blood which a person's heart pumps out per beat. It is measured in unit mL/beat. If you need to know how to calculate stroke volume first before calculating the cardiac output, see the Stroke Volume Calculator.

When multiplied together (heart rate and stroke volume), the unit output resultant will be in mL/min, since beats/min * mL/beat yields mL/min.

Increasing either factor will increase cardiac output, since both have a direct relationship.

To use this calculator, a user just enters in the heart rate and stroke volume and clicks 'Calculate'. The cardiac output will then automatically be calculated in unit mL/min.

When a person is normally at rest, the average heart rate is 70 beats/min and the average stroke volume is 70mL/beat. Therefore, the average amount of blood being pumped is 4900-5000mL/min at rest. During rigorous exercise, this amount increases dramatically. For one, a person's heart beats rapidly during exercise, so the typical 70 beats/min can turn into 200 beats/min or even more. Your body also pumps out more blood. During exercise, your body uses up oxygen more rapidly. Since blood transports oxygen throughout the body, it needs to be pumped and circulated more rigorously throughout the body during exercise. So a person can pump as much as 35,000mL of blood per minute during intense exercise.

The electronic device, a pacemaker, may be used to stimulate heart beats in individuals who have irregular heart beat, which is why it is pictured above.

Example Calculation

If a person has a heart rate of 70 beats/min and a stroke volume of 70mL/beat, what is the cardiac output of this individual?

So based on the values of the parameters, we use the equation CO= HR * SV and substitute in the values into the equation.

CO= 70 * 70= 4900 mL/min