GreenWorks 21142 Review

product image of GreenWorks 21142 10Amp 18-Inch Corded String Trimmer

Our rating: 4 stars Good  

Customer rating: 1500+ reviews *

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Thanks to the brushless motor, the GreenWorks 21142 is a very powerful electric weed eater. It’s designed as a less noisy plus maintenance and fumes-free alternative to gas trimmers, also with a possibility to use various attachments.

* please note the reviews on Amazon are mixed from 3 different tools

  • Very powerful
  • Attachment capable
  • Price
  • Some users report problems with line feed
Key specifications:

(the outlined parts with no fill indicate using edger and brush cutter addons)

Review GreenWorks 21142 Corded String Trimmer

Note: Some of the pictures below actually show the cordless version – the point is just to show the size and handling of this tool.

Brushless motor

the power of the GreenWorks 21142The main difference from common electric weed whackers is that the 21142 is equipped with a brushless motor – which offers greater power and torque, longer lifetime and less noise. The only disadvantage is a slightly higher initial cost (if you are interested how this motor works, take a look at this article).

Power and weight

Keep in mind this unit is intended as a gas trimmer replacement, it’s not a classical cheap and lightweight electric tool! It has a sturdy metal construction which means it’s a little heavier, but the balance is nice and it is still lighter than gas trimmers. Plus it is much cheaper (you’ll only have to buy an extension cord if don’t have one already – see FAQ), a lot less noisy, requires no maintenance or fuel mixing and doesn’t produce any fumes.

Thanks to the brushless engine and large cutting swath, the GreenWorks 21142 is probably the most powerful electric trimmer currently on the market – it cuts tall grass and tough weeds like butter (wearing long pants and glasses is a necessity).

Available attachments

Line feeding and potential problems

The line feeding is performed using a bumping system which works flawlessly most of the time – however, some users also reported problems with it, often even recommending using a 3rd party trimmer head which works perfectly then.

There are no speed settings but that’s not a big deal. What’s worse is the safety switch which could have been designed better. When used repeatedly for a long time, it makes your hands really fatigued – so be sure to wear gloves (if you don’t already).

Also, the plastic wing nut that holds the handle in position seems a bit flimsy – so if you encounter any problems, replace it with a metal one.

Brush cutter attachment in action

Edger and adjustments

As most of other electric grass cutters, this one is equipped with an edger function as well – however, it’s not that great. The safety guard is blocking the sight, there is no guide to keep the right distance from the ground and even the tool itself is quite large and heavy for the task.

On the other hand, the attachment capability is a great plus, particularly if you own some older gas attachments! You can easily convert your machine into a hedge trimmer, blower, brush cutter or others.

The assembly is easy and tool-less and it accepts parts from many different brands, for example Ryobi, TrimmerPlus or Yardworks. Take a look at the most popular here.

The shaft’s length is not adjustable; however, you can set the position of the handle as you like to achieve the right balance (you just loosen the screw and slide it up or down). And it’s pretty comfortable even for tall people.

Conclusion:  If you are searching for a powerful trimmer without the disadvantages of gas machines and don’t mind dragging a cord, the GreenWorks 21142 is ideal for you, particularly if you already have some older attachments. (if you’d like to work rather with batteries instead of a cord, check out the cordless version).

However, if you need a lightweight unit mainly for cleanup or medium-difficulty jobs (possibly with more frequent edging), we would rather recommend you the Greenworks 21272.

>> Read more or buy the GreenWorks 21142 here

edging a path in park      using a blower attachment


  • Amp: 10 Amp
  • Cord lock: yes
  • Weight: 9.9 lbs
  • Cutting swath: 18″
  • Line: 0.08 dual line
  • Feeding: bump feed
  • Warranty: 4-year for non-commercial use
  • Includes: prewound spool, shoulder strap

(compare with others)

Frequently asked questions:

Are there any accessories I should buy?

The line lasts for quite a long time, but if you want a spare one, get for example the high quality 0.08″ Cyclone string. You can watch this video if you need any help with restringing:

   Show Video

Also, if you don’t have a long extension cord yet, you’ll need to get one. For a trimmer this powerful, many users recommend the heavy-duty 12/3 – however, you’ll pay almost as much as the machine’s cost for it and it’s also quite heavy to drag around.

The 21142 uses 10 amps so even the cheaper 100 feet Coleman 16/3 will handle it. But if you plan to use your power cord to drive other yard equipment that has more than 10 amps (lawn mower for example), it’s definitely worth investing in a 12/3 cable (for more information on this subject, take a look at this extensive guide).

Is there any maintenance needed?

No, the motor is an enclosed unit so no maintenance is required. Just clean the machine from dead grass occasionally.


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