Electrical Wiring in the Home/comparing wires


QUESTION: Hello Greg,

I'm comparing two extension cords for 120v and 15amp or less, which of these two wires is thicker (less resistance)?

a wire composed of three separate gauge 14 cables (includes ground)


a gauge 10 wire with ground?

My doubt comes from not knowing how thick are the cables that compose the gauge 10 wire

Thanks, appreciated



ANSWER: If you took three 14 awg wires and connected them together at each end you create about an 8 awg, in affect.

The actual sizes are:

14 awg = 0.064084 inches

10 awg = 0.10189 inches

You cannot simply add up two 14 awg in inches to come up with the correct figure.

So, two 14 awg DOES NOT equal (0.064084 + 0.064084)  0.128168 inches

Hope that helps.

---------- FOLLOW-UP ----------

QUESTION: Dear Greg,

Thank you for your quick response. If I'm understanding your explanation right, the cable composed of three 14 awg wires would be aproximately like an 8 awg wire,and therefore it's thicker than the 10 awg cable... Did I get the idea?

Thank you in advance,


I am not talking about thickness.

In the electrical world we talk about resistance, impedance and ampacity.

A rope is thicker, but has a really high resistance so we do not speak of "thickness".

So, if all three wires are 14 awg and tied properly together they would look like and act like an 8 awg wire to the electrons.  
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Greg Hughes


Troubleshooting electrical including appliances and HVAC.


34 years of experience.

Both college and tech schools in this field.

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