AED vs. Defibrillator: What's the Difference?

If you have shopped for lifesaving equipment, you have probably seen the terms used interchangeably and wondered about the real difference between an AED and a defibrillator. Here is the short answer: an AED is a defibrillator — but not every defibrillator is an AED. Understanding the distinction makes it easy to choose the right device.

What a defibrillator does

A defibrillator is any device that delivers a controlled electrical shock to the heart to stop a life-threatening, irregular rhythm (such as ventricular fibrillation) and give the heart a chance to re-establish a normal beat. “Defibrillator” is the broad category. The differences come down to who operates it and how much it automates.

AED: built for anyone

An automated external defibrillator (AED) is a portable defibrillator designed for lay rescuers and first responders. It analyzes the heart rhythm automatically, decides whether a shock is needed, and guides the user with clear voice and visual prompts. You cannot accidentally shock someone who does not need it — the device will only enable a shock when it detects a shockable rhythm. AEDs come in two styles:

• Semi-automatic: the device analyzes the rhythm and, if a shock is advised, prompts the rescuer to press a button.
• Fully automatic: the device analyzes and, if a shock is advised, delivers it on its own after a warning — removing hesitation from the rescue.

Manual defibrillator: built for clinicians

A manual defibrillator is the type you see in hospitals and on advanced EMS units. The operator — a trained clinician — reads the heart rhythm on a monitor and decides whether and when to deliver a shock, along with the energy setting. Manual units are powerful and flexible but require medical training. They are not intended for the general public.

A note on implantable and wearable devices

You may also hear about implantable cardioverter-defibrillators (ICDs), which are surgically placed in high-risk patients, and wearable cardioverter-defibrillators (vests). These are prescribed personal devices for ongoing protection — different from the public-access AEDs a school, business, or gym would install.

Which one do you need?

For virtually every workplace, school, gym, place of worship, or home, the answer is an AED. It provides the lifesaving capability of a defibrillator in a package any bystander can use under pressure. Explore options across every major brand in our stocked AED collection.

Frequently asked questions

Is an AED a defibrillator?

Yes. An AED is a type of defibrillator designed to be used by the public, with automated rhythm analysis and guided prompts.

Can anyone use an AED?

Yes. AEDs are designed for untrained bystanders and will only enable a shock when a shockable rhythm is detected. Training builds confidence but is not required to operate one.

What is the difference between semi-automatic and fully automatic AEDs?

A semi-automatic AED prompts the rescuer to press a button to deliver a shock; a fully automatic AED delivers the shock itself after a warning.