About stroke volume
Stroke volume (SV) is the amount of blood the left ventricle ejects with each heartbeat. It is calculated as the difference between end-diastolic volume (EDV), the volume of blood filling the ventricle just before it contracts, and end-systolic volume (ESV), the volume left behind right after contraction: SV = EDV - ESV. SV is usually reported in milliliters per beat and is one of the basic building blocks of cardiac function, alongside heart rate and ejection fraction.
The related measurements this calculator reports
- Ejection fraction (EF): EF = SV / EDV x 100. It expresses stroke volume as a percentage of the blood available to eject, and is the number most often used to describe how well the left ventricle is pumping.
- Cardiac output (CO): CO = SV x HR. Multiplying stroke volume by heart rate gives the total volume of blood the heart pumps per minute, usually converted from mL/min to L/min.
- Stroke volume index (SVI): SVI = SV / body surface area (BSA). Dividing SV by BSA normalizes for body size, which makes it easier to compare stroke volume across people of different heights and weights.
Where EDV and ESV come from
In practice, EDV and ESV are measured with echocardiography, cardiac MRI, or ventriculography, and this calculator simply performs the arithmetic on whatever values you enter. Typical resting values for an average adult are roughly 100-150 mL for EDV and 40-60 mL for ESV, giving a resting stroke volume in the neighborhood of 60-100 mL per beat, though exact figures depend on body size, sex, fitness, and the imaging method used.
When to consult a professional
This tool performs the standard stroke volume arithmetic for education and reference; it is not a diagnosis and does not replace an echocardiogram report or a cardiologist's interpretation. If you are reviewing your own results, discuss them with a licensed healthcare provider who has your full clinical picture.