CalculatorHub Search

Ejection Fraction Calculator

Reviewed by the CalculatorHub team, edited by James Graham. AHA/ACC classification criteria for ejection fraction. Last verified 14 June 2026.

Ejection fraction (EF) measures how efficiently the heart pumps blood. It is the percentage of blood ejected per beat relative to the total volume the ventricle holds when full. A normal EF is 55% to 70%. Values below 40% indicate reduced ejection fraction and are classified as heart failure with reduced ejection fraction (HFrEF). You can calculate EF from stroke volume and end-diastolic volume, or directly from end-diastolic and end-systolic volumes.

Ventricular volume when fully filled (mL)
Ventricular volume after contraction (mL)
70.00 mL
58.33%
Normal

Ejection fraction formula

Stroke Volume (mL) = EDV - ESV
Ejection Fraction (%) = (SV / EDV) x 100 = ((EDV - ESV) / EDV) x 100

Where EDV is end-diastolic volume and ESV is end-systolic volume. The AHA/ACC 2022 heart failure guidelines define: normal EF as 52-72% (men) or 54-74% (women) by 2D echocardiography. For general clinical use, 55-70% is used as the normal range.

Ejection fraction classification (AHA/ACC)

  • Normal: EF 55% or above
  • Mildly reduced (HFmrEF): EF 41% to 54%
  • Reduced (HFrEF): EF 40% or below
  • Preserved (HFpEF): EF 50% or above with diastolic dysfunction (requires clinical evaluation)

Ejection fraction calculator: frequently asked questions

What is ejection fraction?

Ejection fraction (EF) is the percentage of blood that the left ventricle pumps out with each heartbeat: EF = (Stroke Volume / End-Diastolic Volume) x 100. A normal ejection fraction is 55% to 70%. It is a key measure of how well the heart is functioning as a pump.

What ejection fraction is considered normal?

An ejection fraction of 55% to 70% is considered normal. An EF of 41% to 54% is mildly reduced (previously called mildly abnormal). An EF of 40% or below is classified as reduced ejection fraction (HFrEF), which is heart failure with reduced ejection fraction. These classifications are defined by the American Heart Association and American College of Cardiology.

How is ejection fraction measured clinically?

Ejection fraction is most commonly measured by echocardiography (ultrasound of the heart). It can also be measured by cardiac MRI, nuclear stress testing (MUGA scan), or cardiac catheterization. The echocardiography methods include the biplane Simpson method (most common) and the Teicholz method.

Can ejection fraction be too high?

Yes. An ejection fraction above 75% may indicate hypertrophic cardiomyopathy, in which the ventricular walls thicken and reduce the chamber volume. Heart failure with preserved ejection fraction (HFpEF) occurs when the EF is above 50% but the heart cannot fill with blood properly (diastolic dysfunction). High EF alone is not necessarily better than normal EF.

What treatments can improve ejection fraction?

Medications that improve ejection fraction in heart failure include ACE inhibitors, ARBs, beta-blockers, aldosterone antagonists, and SGLT2 inhibitors. Cardiac resynchronization therapy (CRT) and implantable cardioverter-defibrillators (ICDs) are used in selected patients. Lifestyle changes including smoking cessation, reduced salt intake, weight management, and regular moderate exercise also help.

Official sources

Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.