The extension cord is very important when buying an electric lawn mower with a cord. Your quality of cut is directly affected depending on the length and size of the cord. This page is probably the most important one you will run into while looking for a corded electric lawn mower.

This pdf will help with choosing the right cord. On many pages at Amazon I find people buying 16 gauge cords that are 100 ft long. I could not find a single electric lawn mower where this would be adequate. Do your mower and your pocketbook a favor and buy the right cord. You prematurely wear out your brushes and risk burning out the motor when using the wrong size cord. Feel free to download this PDF.

If you would like to see how to use the PDF I walk through a couple examples on my post about buying the best extension cord for an electric lawn mower. This works for all power equipment, not just electric lawn mowers.

Best Corded Electric Lawn Mower 2019

So I need at least a 14G cord, but I can NOT find this cord in two prong anywhere, is it safe to use a 3 prong on a two prong mower? I have the SUNJOE 12 amp. Please help!

So I need to know how long of a cord you need? I need to find the manual as the model is now here – https://amzn.to/36qhAtf

OK, looks like a 3 prong will work fine. I suggest you go to this page – https://amzn.to/383VTQk – and scroll down to the videos and watch the second one. It is a customer video and if you go to around the 4:20 mark you will see he plugs in a 3 prong cord. As far as the cord goes I would still need to know how long of a cord you need. If its only 50 ft 14 gauge should be fine. If you are going 100 ft you will need a combo or just a 100ft 12 ga like this one – https://amzn.to/3MfxA0m

Also, just so you know, as long as the cord will fit a 2 prong connector is perfectly safe using a 3 prong cord. I also can not find a 14/2 extension cord rated for outdoor use.

Are you looking at the 14, 16 or the 20 inch?

How do you know what is the gauge of the extension cord either 120 or 150 ft long? lime green color. On the two prongs plug, I found U 08 VV, TA4E74893, 5. On the shiny label, I found UL, C, US, Listed general use extension cord, No. Z40315183, 10 A, 125V, 1250 W, 0096473L9, E74893.

Is this extension cord compatible with Greenworks push corded 16 inch 10 amp lawn mower?

That may have additional markings. I see no indication that tells the gauge. Look for a 14/2 or 16/2. Some of the markings could just be molded into the cord without contrasting color. if you have some chalk, or a small piece of drywall you could rub that on the area to make it easier to read.

See this page https://www.totalmower.com/buy-the-best-extension-cord-for-your-electric-mower/ for additional info.

I see you found some added info. Have you figured it out yet?

My yard is 100 ft from back patio or front porch to the corner of the fence. The distance from the wall plug to the patio may be 25 to 50 ft. What combination of extension cable is more cost saving?

Greenworks model 25012 Electric corded mower 18 inch with 12 Amp motor costs $149.

Should I buy three 50 feet 12/3 gauge extension cord, which will yield 5.76% drop? 5.76% drop is over the 5% voltage drop rule.

For 12 gauge extension cable chart, use the 15 amp column, 50 ft row:

% drop per amp = divide 1.6% drop by 10 amp column = 0.16% drop per amp

0.16 x 12 amp = 1.92% drop of voltage

Each 50 ft of 12ga @ 12 amps gets 1.92% drop of voltage.

Total of three 50 ft extension cables gets 1.92% x3 = 5.76% drop of voltage.

Cost of one Southwire 2588SW0002 Outdoor Cord-12/3 SJTW Heavy Duty 3 Prong Extension Cord-for Commercial Use (50′, Yellow), 50 Feet is $33.

The cost of three 50 ft of 12 gauge extension cable IS $33 X 3 = $99

cost of two Hot Headz H-EXT-302 Outdoor Extension Safety Seal Resistant Cord $6.99 x2 = $14

total cost of extension cables and extension safety seal resistant cord is $113 = $14 + $99

total cost of corded mower plus extension cables and extension safety seal resistant cord is $262.

Is my calculation of loss of voltage correct? What combination of extension cables would you recommend?

I found your answer regarding combination of two different gauges of extension cables for 12 AMP motor.

Leiif Aurumsonn August 16, 2018 at 9:30 am said:

Assuming you have a 12 AMP motor the max you could go with 12ga cords would be about 135 ft.

After that you are over the 5% rule and risk burning out the motor.

If you need 150 ft. go with a 50 ft 10ga cord ( here – https://amzn.to/2MjtxFV ) and the 100 ft 12 ga cord ( here – https://amzn.to/2tRLWxo ). You may also need a good connector like this ( https://amzn.to/2PfKjDM ).

For 12 gauge extension cable chart, use the 10 amp column, 100 ft row:

% drop per amp = divide 3.2% drop by 10 amp = 0.32% drop per amp

For 12 Amp motor: 0.32 x 12 amp = 3.84 % drop of voltage

100 ft extension cord of 12ga @ 12 amps gets 3.84% drop of voltage.

For 10 gauge extension cable chart, use the 10 amp column, 25 ft row:

% drop per amp = divide 0.5% drop by 10 amp = 0.05% drop per amp

For 12 Amp motor: 0.05 x 12 amp = 0.6 % drop of voltage

25 ft extension cord of 10ga @ 12 amps gets 0.6% drop of voltage.

For 10 gauge extension cable chart, use the 10 amp column, 50 ft row:

% drop per amp = divide 1% drop by 10 amp = 0.1% drop per amp

For 12 Amp motor: 0.1 x 12 amp = 1.2 % drop of voltage

50 ft extension cord of 10ga @ 12 amps gets 1.2% drop of voltage.

Total voltage drop for 125 ft cord: 100 ft of 12 ga + 25 ft of 10 ga extension cables gets 3.84% + 0.6% = 4.44 % drop of voltage.

Total voltage drop 150 ft: 100 ft of 12 ga + 50 ft of 10 ga extension cables gets 3.84% + 1.2% = 5.04 % drop of voltage.

Total cost of extension cord 125 ft: 100 ft of 12 ga + 25 ft of 10 ga = $69.93 + $49.99 = $119.92

Total cost of extension cord 150 ft: 100 ft of 12 ga + 50 ft of 10 ga = $69.93 + $69.99 = $139.92

ProStar 10 Gauge SJTW 3 Conductor 50 Foot Extension Cord With Lighted Ends – Orange $69.99

Iron Forge Cable 25 Foot Lighted Outdoor Extension Cord – 10/3 SJTW Yellow 10 Gauge Extension Cable with 3 Prong Grounded Plug for Safety, 15 AMP – Great for Garden and Major Appliances $49.99

Southwire 25890002 2589SW0002 Outdoor Cord-12/3 SJTW Heavy Duty 3 Prong Extension Cord, Water Resistant Vinyl Jacket, for Commercial Use and Major Appliances, Foot, Yellow, 100 Feet, Ft $69.93

Sorry for the slow reply. Did you figure it out yet? Be aware the 10ga cords can be heavy. I would mow as far as possible with just the 12 ga first then add the 10 so you don’t have to carry it. Also see the page about using a corded mower here: https://www.totalmower.com/mowing-with-a-corded-electric-lawn-mower/

Please confirm that my calcualtion for the loss of voltage is correct. Then I would not buy the wrong combination of extension cords with different gauage. I just need a double check of my calculation.

Thank you for creating this totalmower.com website for consummer. It helps me to determine to buy a corded lawn mower.

Your calculations are correct. Your best option looks to be 1 12ga at 25ft and 1 12ga at 100ft. If you have to have 150 ft you need to go to 10ga on the 50ft or you are over the 5% limit and risk burning up the motor.

12ga 100ft – https://amzn.to/3IPSnpo

12ga 25ft – https://amzn.to/36vFGmB

10ga 50ft – https://amzn.to/3NylLDZ – orange is least expensive

If you won’t be pulling against the connection you may not need the connector and be sure a 10ga will fit in a connector if you have to have the 50ft 10ga wire. Hopefully you only need the 25ft. Be sure and actually measure that distance from the outlet to the edge of the porch. Hope that helps.

What size of a outside extension cord do I need for a 20″ 13AMPS B & D Lawn Mower? It needs to be 100 feet long.

You would be best served by a 12 ga extension cord. That would give a 4.16% voltage drop which is under the 5% limit. The 13amps makes it a little more than 5%, actually 5.33% drop if you did a combo of 12 and 14.

Hello, I have a craftsman lawn mower, 10 amps and I need at about 80′. Would a 24m (78′) 16 gauge be fine? or should i go with 14 gauge? thanks

Sorry for the late reply. Go with the 14 gauge.

13 AMP SUNJOE LAWNMOWER. can you let me know what cord I could buy at home depot. i will need a 100′ cord

You will need a 12 gauge cord to safely run 100 ft.

Best price on Amazon – https://amzn.to/2UXTnni

Second Best – https://amzn.to/2V2eyEU

Be sure and check HD online as my local HD does not have anything

in stockthat matches this price.Comments have been made about connecting 2 or more heavy duty cords together. How much voltage drop should be considered for each connection (if any)? Normally, it is not recommended to “daisy chain” extension cords, but it is very hard to find 150 ft heavy duty cords. In one example above, you suggest a “50 ft 10ga cord and the 100 ft 12 ga cord”–which should be plugged into the outlet first?

I would plug in the 10ga first and use a good connector (https://amzn.to/2PfKjDM). Also make sure the outlet is a 20amp rated outlet, which will mean it is wired with 12ga solid wire and NOT 14ga.

I have a craftsman corded electric mower, which works very well. It appears that I should use at least a 12 gauge wire, rather than the 14 that I have used, for 100 ft. however I would prefer to have a longer cord. Can I hook two cords together to get 150 or 200 ft length? Would 12 gauge still be OK or should one have 10 gauge?

Is there a limit to cord length and why

Thank you.

Sorry about the delay. Can you tell me the AMP rating of the mower? I can NOT do the figures without the amps.

Assuming you have a 12 AMP motor the max you could go with 12ga cords would be about 135 ft. After that you are over the 5% rule and risk burning out the motor. If you need 150 ft. go with a 50 ft 10ga cord ( here – https://amzn.to/2MjtxFV ) and the 100 ft 12 ga cord ( here – https://amzn.to/2tRLWxo ). You may also need a good connector like this ( https://amzn.to/2PfKjDM ). 200 ft is overdoing it and the cords would cost more than the mower. You would need 2, 10 ga cords for that distance. They are heavy and expensive.

I have 13in 11 Amp electric lawn mower. I believed 14/3 extension cord should be fine. But some article recommend 12/3 is it necessary?

Sorry about the long delay. For some reason I never got a notice about your comment. How long of a cord are you using? Length matters as much as size. 11 amps is not so big so 14/3 should be fine up to 90 ft. The problem is there aren’t 90 ft cords. At 100 ft you are at about 5.6% voltage drop. That is over the recommended 5%. I would use a 50 ft 12ga and a 50ft 14ga with a quality connector (https://amzn.to/2PfKjDM) to keep them together. If you only need 75ft then 14ga is plenty.

I read PDF, watched the video, read all information including comments from people who purchased GreenWorks. My GreenWorks 20” 12 AMP Electric lawn Mower 25022, arrived this evening. Read the Minimum Gauge For Extension Cords Chart. The only thing I didn’t see from other comments was about the Chart stating that the 100’ cord was not recommended.

My extension cord I bought previously is 12/3 for leaf blower and trimmer.

Is it still ok to use the 100’ based on everything else I read?

Short answer. YES. 12ga should be fine for 12 amps at 100 ft.

Hi, For a Greenworks model 25112 electric mower it sounds like I would need a 12/3 gauge cord for 100Ft needed. Is this correct?

Yes, that puts you at 4.16% voltage drop which is still in a good range. This one is on sale at Amazon right now -> https://amzn.to/2tRLWxo

That is a better price than in my post on Buying the best cord – https://www.totalmower.com/buy-the-best-extension-cord-for-your-electric-mower/ Don’t buy green. Make sure it is very bright.

Hi I have a Greenworks 25022 Electric mower. I currently have a cord that’s 100 ft long and is 12/3. Would I be able to get away with a 100 ft cord that is 14/3?

I need a new extension cord because the one i purchased a few years go has many kinks that I can’t unravel. Thanks for your help!!! 😀

Sorry for the delay. It is 12 amps so you would be over the 5% rule with a 14ga. You might try untwisting your current cord first. If that can’t be done then go for a new 12ga like this one HERE. Also do NOT miss the article on buying a cord and the article on mowing with a cord.

Hi, I have the Greenworks 25022 and I love it! I’m a bit confused about the type of extension cord. I currently have a 100ft 12/3, which i’ve used for the past 3 years. It has so many kinks and is twisted up I figured I should buy a new one. If I’m understanding the cord recommendations in the manual – it looks like they actually do not recommend a 100 ft 12/3, but instead a 100ft 14/3. Is that accurate?

Sorry for the delay. It is 12 amps so you would be over the 5% rule with a 14ga. You might try untwisting your current cord first.

You are correct in stating that the manual says a 14ga is OK. I would NOT do that though. Using the PDF above the 14ga wire at 100 ft is already at 5.1% at 10 amps. If you add 2/10th more for the next 2 amps you get 6.12% voltage drop for 12 amps at 100 ft. That is too far over to work well for the motor. You are taking a risk that the motor will burn out. Better to be safe than sorry. I will call Greenworks and direct them to this post. In my estimation that is an error in the manual. This PDF was done by an electrical engineer with a focus on safety. I would trust this guide more than the manual.

So, based on the chart, it sounds like a 100-ft 12/3 should be okay for the kobalt km 210 (13 amp) mower? Is that right?

Yes, that is correct. The actual drop is 4.16% so it is under the 5% rule and should be fine.

The worx 12 amp wg720 lawn mower says 12 gauge at 50 ft, does not recommend 100 ft. I have a 12/3 15 amp 100 ft cord I need that size for my yard. it does this mean this will not work? I don’t understand it only is 12 amps and my cord has plenty watts.

That should work fine. It is below the limit of 5% voltage drop at 3.8% so should be fine. Just be sure it is 12ga and you should have no problem. Check the fine print on the cord itself. If its hard to see rubbing chalk over the indentation should help.

Getting a 13 amp sun Joe 17 ” …..need 100 feet plus 25 more. Should both be 12/3

Say 100 feet plus 25 feet same make cord?

Could I do 100 feet 12/3 & 25 feet 14/3 ?

Wow, pricey !

Thank you

Going thru the numbers and I get that as a bit too much over the 5% voltage drop rule.

25 ft of 14ga @ 13 amps gets 1.625% drop

100 ft of 12ga a@ 13 amps gets 4.16% drop

added together and you are at 5.785% voltage drop.

SO, I would say get both 12ga cords to be closer to that 5% rule. You still are over but only by .07 %. Its the length that is making it difficult but better safe than sorry. The other option would be 3 cords: 50ft 10ga, 50ft 12ga and 25ft 14ga. That still is over but now only by .005%. 10ga cords are really pricey https://amzn.to/2EbCeJv

Gosh….cord is a much as the mower!

Does it really matter if the mower is 12 Amps or 13 amps? Still using a 12 /3 cord?

And thank you….so much! Happy Easter.

Cindy

Corded is my only option….can not push gas mowers!

Each amp is adding just a bit more. So, yes, it all adds up. Length and amps call for the need to have a bigger wire. Happy Easter to you also.

Ok…one last question….should I go with SunJoe 403E 13 amp 17″ 2 in 1

Or……Greenworks 25022 12amps 20″ 3 in 1

Many thanks..

Was away. Let me look it over. Will edit this reply with answer in an hour or so.

O.K. Here is what I would say. First and foremost the decision is yours to make and typical disclaimers apply. Taking the facts from the reviews and the warranties into account I would be split down the middle. They both occasionally have issues right out of the box. Looking deeper the Greenwise has 30 times more reviews and is still at 4.3 stars. That is good. Also you mentioned 125 ft of cord would be needed. That is a larger yard and the extra 3 inches of width will make a huge difference. In your case I would lean towards the Greenwise. Hope that helps.

I updated the previous reply but want to add a bit. Be sure and realize the cord is an issue for some but not bad once you are used to it. Read my post on Mowing with a corded mower. Be prepared for a struggle the first few times you use it and always mow MOVING AWAY from the plug.

thank you friend…you have been so very helpful

Cindy

Thank you so very much for your wealth of knowledge on thus subject.

My delima is….my yard really isn’t that big, but I do t have an outdoor outlet so it needs 25 ft to get to the lawn. Lawn us only 50ft X 50 ft.

Again, appreciate your advice

So 1, 100 ft cord should be all you need. Get a 12ga extension cord and you have plenty of power for either mower.

thank you friend…you have been so very helpful

Cindy

Hi,

I am buying a Greenworks 18 inch 12 amp electric mower, and I was thinking that a 50ft one will do. What should I get?

Thank you so much!!!!!!!!!!!!

If its only 50 ft a 14 gauge will work fine.

If you are going 100 ft I would get a 12 gauge.

If you get a 50 ft 14 gauge and decide you need a bit more length make sure the add on is 12 gauge.

All explained in the PDF and the page https://www.totalmower.com/buy-the-best-extension-cord-for-your-electric-mower/

I have a Greenworks 16 in. 10 Amp Corded Electric lawn mower, I believed 14 gauge 50 feet extension cord should be fine. But some article recommend 12 gauge, is it necessary?

For 10 amps at 50 ft you are fine.

I purchased a Greenworks 16″ 10 AMP Electric Lawn Mower model 25142.

Manual states:

For 50′ cord, use 16 AWG

For 100′ cord, use 14 AWG

For 150′ cord, use 12 AWG

Can I use a 50 ft. 14 AWG extension cord that I currently have or do I need to purchase a new 50′ 16 AWG cord?

You can use the 14 gauge you have as it is a bigger wire than a 16 would be.

Thank you for your speedy reply! 🙂

Go to garage sales and sometimes see extension cords for sale. How can you tell what gauge it is.

Hi Jill,

Almost all round cords have the specs on the wire. It is hard to see but look closely and you will see every foot or so a group of numbers, letters and other code. The cord construction section of the PDF is what the codes will be like, however it will all be in one line on the edge of the cord. Usually it is an uncolored indented font. Take a piece of chalk with you to the flea market and you can rub it into the font to see it clearer. Hope that helps.

Leiif

I have a Black and Decker MM2000 electric mower. I am currently using a 50 foot 12/3 extension cord. Unfortunately, for my front yard, I really need about an extra 5 feet. Should I just buy a short 12/3 gauge extension cord and attach it to the cord I’m currently using? My manual for my mower say it is not recommended to use anything more than a 50′ cord.

The MM2000 mower draws 13 amps.

You would be fine with an additional 25 ft. That could be a 14 gauge and you would still be fine.