At AboutMechanics, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

What is an Extension Cord?

An extension cord is a length of flexible electrical cable with a plug on one end and one or more sockets on the other. It allows you to power devices at a distance from the main outlet, enhancing convenience and reach. Curious about how to choose the right one or use it safely? Discover the essentials in our comprehensive guide.
B. Turner
B. Turner

An extension cord is a type of electrical wiring used to extend the length of a power cord. A standard extension cord consists of one or more metal wires protected by a plastic or PVC insulation coating. One end of the cord features an input plug for electrical devices, while the other features a pronged-plug that can be inserted into a wall outlet. These cords allow users to power objects located far from an electrical outlet, or even objects located outdoors.

Extension cords come in many lengths and sizes to suit the needs of different users. Generally, buyers choose a short cord for convenience and ease of use on small jobs, while long cords may be needed for projects located far from a power outlet. Contractors and others who use an extension cord frequently may purchase several cords in varying lengths to accommodate different types of projects. Thicker cords typically contain thicker wires, leaving them capable of transferring higher electrical loads. Thinner cords, on the other hand, contain fewer wires, and are designed to handle lighter power loads.


Each extension cord is designed specifically for use indoors or out. A cord rated for outdoor use can safely be used indoors, but an indoor cord should never be used outside. Cords with an industrial rating are designed to withstand use around oil, chemicals, or other materials likely to cause corrosion.

Before choosing an extension cord, buyers should check the electrical plug to determine which cords will work with different types of appliances. Some basic lighting and appliances utilize a two-prong outlet, while microwaves and other large appliances require a three-prong outlet. This third prong acts to ground the cord, so cords with missing grounding prongs should not be used. Some specialty applications may even require an extension cord with a twist-lock connector, or other specialized prong design.

In addition to basic extension cord designs, some cords include special features that add convenience and versatility. While most cords power only a single appliance, some contain a special power strip that can be used to power two or more fixtures. This power strip often comes with its own on-off switch to help save power when the appliances are not in use.

Wireless extension cords offer a convenient alternative to traditional cords. To operate these units, users plug the base of the cord into any wall outlet. The base transmits power to a receiver unit using microwaves or radio waves. Users can then plug items into the receiver to power them without the use of wires.

You might also Like

Discussion Comments


@orangey03 – The absolute best way is to use an extension cord reel. This is like a garden hose reel.

You just lay the cord across the reel and start winding the handle. It will do all the rolling for you. Also, it makes unrolling the cord much easier when you are ready to use it again.

If you don't want to buy a reel, the next best way is just to loop it in the air, using only your fingers. Start by grabbing one end and holding it while you make a big loop, and grab each length of cord at the top until you have one big roll on your hands.


I have a question about storing extension cords. What is the best way to roll them up?

I usually just bend my elbow and wrap them from under my upper arm to the area between my thumb and forefinger over and over. However, the cord has started to look a little twisted, and I think that might not be a good thing.

Does anyone have any advice on how to quickly and easily roll up a cord? I hope I haven't done too much damage already. Since it still works, I probably haven't.


@cloudel – I don't think it would harm your appliances. I use a really thick electrical extension cord just for powering my little vacuum cleaner, and I haven't had any problems with it.

I think that you would only experience problems if you used a cord that was too thin for a job that needed more power. That's just my guess, though.

I use my brother's big orange extension cord when I vacuum my car. I have a little shop vacuum with a short cord, so even if I had an outlet right next to my car, I would probably still need the extension cord.


My husband does a lot of construction work, so he uses heavy duty extension cords. They are thicker than the ones I am accustomed to using.

He needs them to power items like his drill and his saw. When you are cutting through thick chunks of wood, I would imagine you would need a lot of power, and these big cords can surely deliver it.

I'm almost scared to use one just to power one of my small kitchen appliances. I don't know whether or not it would be bad for it, but I feel safer just using a thinner, shorter extension cord.

Post your comments
Forgot password?
    • Worker