Cardiac Output Calculator
Calculate cardiac output — the volume of blood your heart pumps each minute. Enter heart rate and stroke volume, and this calculator multiplies them (and converts to litres) to give cardiac output in L/min, with how it compares to the normal resting range.
Rates and fees change frequently. Always confirm the current figures
with the official authority before relying on this result.
- Educational estimate. True measurement requires clinical methods (e.g. echocardiography).
Formula
Cardiac Output = Heart Rate × Stroke Volume
- Cardiac output is the blood volume the heart pumps per minute.
- CO = heart rate (bpm) × stroke volume (mL/beat); dividing by 1,000 converts mL/min to L/min.
- A typical resting value is about 4–8 L/min.
- Both a faster heart rate and a larger stroke volume raise cardiac output (e.g. during exercise).
- Stroke volume is the blood ejected per beat; it depends on filling, contractility, and afterload.
- This is an educational estimate; true measurement uses methods like echocardiography.
HR 70 bpm, SV 70 mL/beat
Inputs
- Heart rate: 70 bpm
- Stroke volume: 70 ml/beat
Cardiac output = 70 × 70 = 4,900 mL/min = 4.9 L/min, which is within the normal 4–8 L/min resting range.
Frequently asked questions
What is cardiac output?
It's how much blood the heart pumps per minute, found by multiplying heart rate by stroke volume. It reflects how well the heart is meeting the body's demand for blood.
What is a normal cardiac output?
At rest, roughly 4–8 L/min for an adult. It rises substantially during exercise as both heart rate and stroke volume increase.
What is stroke volume?
The amount of blood the heart ejects with each beat, typically around 60–100 mL. It's influenced by how full the heart is, how hard it squeezes, and the pressure it pumps against.
How is cardiac output measured clinically?
Through methods such as echocardiography, thermodilution, or other monitoring. This calculator gives an estimate from entered values, not a clinical measurement.
Related calculators
Stroke Volume Calculator Stroke Volume Calculator is a health and wellness calculator that helps you calculate the volume of a three-dimensional shape or container. The formula used is: SV = Cardiac Output ÷ Heart Rate (or) SV = EDV − ESV. Enter values using the units shown next to each input field (e.g. kg, cm, years). Cardiac Index Calculator Calculate cardiac index (CI) — cardiac output adjusted for body size. Enter cardiac output and body surface area, and this calculator divides one by the other to give CI in L/min/m², along with where it sits relative to the normal range. Mean Arterial Pressure (MAP) Calculator Mean Arterial Pressure (MAP) Calculator is a health and wellness calculator that helps you calculate a blood-related health metric. The formula used is: MAP = Diastolic + (Systolic − Diastolic) ÷ 3. Enter values using the units shown next to each input field (e.g. kg, cm, years).