Greenworks 21142 Review: A Corded Trimmer with an 18-Inch Cut

The Greenworks 21142 is a reminder that choosing electric does not have to mean buying batteries. It plugs into an outlet and offers a wider cut than many compact cordless trimmers. The question is whether moving a cord around your particular yard will be a small inconvenience or the part of trimming you dislike most.

This is a research-based review using manufacturer information, published review details, and owner questions. We have not personally tested the 21142. Research checked September 6, 2026.

The Short Answer

The 21142 is worth considering for a homeowner with a reachable trimming route who wants a corded tool with an 18-inch cutting path. Its dual-line bump head and attachment-capable design give it a different role from a small battery trimmer used mainly for a few patio edges.

We would check two things before ordering: the cord route and access to the correct head parts. Owner questions show that identifying and restringing the head can be confusing, especially on used units. This is a conditional recommendation for a suitable yard, not a claim that the widest cutting path automatically finishes every job fastest.

Greenworks 21142 — 10-amp, 18-inch corded string trimmer

Corded trimming and attachment checks

Greenworks 21142

Plug-in model; no battery is needed. Budget for a suitable outdoor extension cord if you do not already have one. As an Amazon Associate, we earn from qualifying purchases.

Check current price at Amazon →

The Specifications and Their Limits

Greenworks’ Canadian manufacturer page identifies SKU 21142 and supplies these core features. The US Amazon listing matches the basic model description. Regional support and warranty terms should be checked for the US purchase rather than copied from the Canadian page. Greenworks 21142 information, US Amazon listing.

An 18-inch swath describes the cutting circle, not guaranteed productivity. Near a narrow bed edge or around obstacles, control and positioning matter more than using the entire width. A wide swath is most relevant where there is room to use it.

What We Could Verify from Review Evidence

Consumer Reports’ publicly indexed review description identifies the 21142 as a 10-amp corded trimmer. Its test-comment preview notes easy starting and describes the 9.7-pound tool as heavy for a corded model. We did not access the full test results, so we are not assigning a cutting score or claiming that it beat other models. Consumer Reports’ 21142 review page.

That limited evidence makes working comfort worth considering. Avoid judging the machine only by a retailer’s “lightweight” description. Hold a comparable setup in a working position if possible, and account for the cord you will be moving along with it.

We also found an owner who bought a used 21142 and could not work out how to open the head to restring it. That is a documented usability question, not proof that every original head is difficult or defective. A used trimmer may also have a replacement head fitted. Owner’s 21142 restringing question.

Check the Head Before You Need More Line

Find the manual and identify the fitted head when the tool arrives. Understand how to advance the line and how to reload it; those are separate operations. Disconnect power before handling the cutting head, and follow the model’s instructions rather than improvising while it is connected.

Greenworks has a US product page for a T-type replacement head identified for the 21142. That is a useful support reference, but a listed part is not a promise of current stock or compatibility with every altered used unit. Greenworks’ 21142 head reference.

This check takes little time compared with stopping halfway through a job because the spool is empty and you have neither the right line nor the instructions. The motor is only part of owning a trimmer; the head and consumables are what you handle repeatedly.

Measure the Cord Route, Not Just the Yard

Walk from the outlet along the path the cord would actually take. Gates, raised beds, and the far side of a shed can add distance or make repositioning awkward. Choose an outdoor cord that meets the manual’s length and electrical-capacity requirements, and follow its electrical precautions.

Keep the cord clear of the cutting area and maintain awareness of it as you move. If you are continually unwinding it from obstacles, cordless freedom may be worth the battery cost. If the route is open and uncomplicated, plugging in may fit your routine well.

Include the cord in the purchase total. This is the cost of a usable setup, just as a cordless comparison should include the batteries and charger you need.

Attachment Capability Is Not Universal Approval

The product is advertised as attachment capable, but verify the exact accessory against the powerhead and attachment instructions. Brand names alone are not enough. Do not infer that an unlisted cutting blade or brush head is safe because another attachment fits the shaft.

If an edger attachment is your main goal, compare the complete setup with a separate edger. Our trimmer versus edger guide explains when the extra function is useful.

Is It the Right Buy?

Compare the EGO ST1623T if cord management is the sticking point. Consider the WORX WG163 for light work where a smaller tool is more appealing.

The 21142 makes the strongest case when your outlet access is simple and you are comfortable with its head, weight, and support options. Choose it because a cord works for your yard, not solely because the cutting width looks large for the price.