I have a 12 amp electric lawn mower, I have used a 25' 14ga extension cord which worked well. My question is can I plug two 25' 14ga extension cords together to equal 50'? Or would it be better to use 12ga. Extension cords. Can I mix gauges, say a 25' 14 ga. Plugged into a 12ga 50' cord to obtain 75', or is it a no-no to mix gauges? Thanks for your help, j. beck

What is the farthest you want to go? Its best to stick with just 1 extension and for high amps the 12ga is fine.

Hello, thank you for your response. I would like to have at least 100' if that's possible, j.beck

You should be able to find it in that length.

Someone will yell at me, but I've never been picky about gauge of extension cord, or connecting them together. I just use what's handy. After all, they're only temporary.

#14 at 50' is a good number. It gives you a 3.2% voltage drop. One cord or two, it doesn't matter. You should be shooting for 3% or less.

#12 at 50' would give you a 2% drop or 2.4 volts.
#14 at 25' would give you a 1.6% or 1.9 volts
Combined would give you (2.4+1.9)/120 would be ~3.6% which isn't too bad.
#12 at 25' would give you 1% or 1.2V

So, lets look at: #12 at 50' + #12 at 25' + #14 at 25'
(2.4+1.2+1.9)/120 = 4.5% not great

#10 at 50; is 1.3% or 1.5 V
So, let's look at:

50' of #10 + 25' of #12 and 25' of #14
(1.5+1.2+1.9)/120 = ~3.8%. Much better.

Use any combination and you can keep the smallest diameter (#14) wire at the mower. 50' of #10, you might have to make and not buy.

I have 100' of #12 flat style from Woods and it's heavy. Take a look at Woods Wire and cable products manufacture | Coleman Cable, Inc..

I think this Amazon.com: Woods 2991 Yellow Jacket 50-Feet 10/3 SJTW Yellow Power Cord with T-Blade Plug 20-Amp/125-Volt Rated with PowerLite Plug: Home Improvement which is #10 at 50' would be an excellent choice for the 50' segment and it would do better in the voltage drop calcs.

So use the 25' #14 for a while and

then 25' of #14 and 25' of #12 to get to 50'

Then 50' of the #10 and 25' of #14 to get to 75'

and then 50' of #10, 25' of #12 and 25' of #14 to get to 100'

Only glitch is that the #10 at 50' would requite a 20A outlet to plug into. The female end accepts bot 15 and 20 Amp plugs.