Practical Greenworks 40V 12 Cordless String Trimmer Review
I’ll be honest—yard work was never my favorite weekend job here in Austin, Texas. But after trying the Greenworks 40V 12 Cordless String Trimmer, I found myself looking at trimming in a whole new way. I’ve used it on my own lawn, and it feels like swapping an old, heavy toolbox for something light and smart that actually makes the task easier.
I’ve also worked with auto-feed and bump-feed trimmers before, and this one feels smoother in daily use. In this Greenworks 40V 12 Cordless String Trimmer review, I’ll share what worked, what didn’t, and why it might fit your yard care routine too.
My Real Life Experience: Greenworks 40V 12 Cordless String Trimmer Review
When I first picked up a Greenworks cordless trimmer, I wanted to see if it could really match the ease and promise of “no gas, no fuss.” After using it through different seasons, I can share what stood out to me and where it could be better. Think of this as a chat with a neighbor who has already tried it out.
Assembly and Weight – ⭐ 9/10
Putting it together was simple. No toolbox drama, no confusing steps. Within minutes it was ready to use. The weight is light compared to gas trimmers. At around seven pounds with the battery, it feels closer to carrying a broom than wrestling with a machine. For longer jobs, that difference matters.
Power – ⭐ 8.5/10
For a battery tool, the power surprised me. It chewed through tall grass and weeds without stalling. Is it as tough as a commercial gas trimmer? Not quite. But for the average lawn, it feels more than enough. Think of it like a compact car—it won’t tow a trailer, but it will get you where you need to go without burning extra fuel.
Bump Head – ⭐ 7.5/10
The auto-feed head works most of the time. I like not having to stop often to adjust the line. Still, I noticed if I pushed it too hard into heavy weeds, the line wore down fast. A quick bump and it was good to go again. Not perfect, but far less hassle than rewinding by hand.
Vibration – ⭐ 9/10
This is where I noticed a big difference from gas models. The vibration is low, almost soothing compared to the buzzing shake of older machines. My arms didn’t tingle after finishing the yard, which made trimming less of a chore.
Balance – ⭐ 9/10
The trimmer feels well-balanced. The handle and guard placement give it a natural swing. I could trim along fences and flower beds without much strain. If you’ve ever fought with a tool that keeps tipping one way, you’ll appreciate the balance here.
Battery Life – ⭐ 8/10
One full charge gave me about 30 minutes of trimming, which covered my whole lawn. For larger yards, you may need an extra battery. The good news is the same battery fits many Greenworks tools, so if you already own one, you can swap and keep going.
Sound Level – ⭐ 9.5/10
This is one of the best parts. The sound is low, more of a hum than a roar. I could trim early in the morning without worrying about waking the neighbors. Compared to gas, it feels like the difference between a vacuum and a motorcycle.
Add-On Capacities – ⭐ 9/10
Greenworks makes a range of tools that run on the same 40V battery. That’s a nice bonus. I started with the trimmer, but I can see how useful it would be to have a blower or mower on the same system. It feels like buying into a family of tools that work together.
More About the Battery Life / Runtime – ⭐ 8/10
The battery charges in about an hour, which is quick. Still, runtime is tied to how tough the job is. Thick weeds and tall grass can drain it faster. For light trimming, it lasts longer than expected. Having a spare battery is like carrying an extra water bottle on a hot day—you may not need it, but it keeps you safe.
What I Struggled With, and How It Could Be Better
The main struggle was with the thin trimming line. For light grass it’s fine, but thick patches chew it up quickly. Also, the battery life, while good, won’t always stretch across larger properties. If Greenworks made a slightly tougher line and gave a little more runtime, it would be close to perfect.
What I Like About This
I like the freedom from gas and cords most of all. It feels lighter, quieter, and cleaner than what I was used to. The push-button start is a small thing, but when you’ve fought with a pull cord on a hot day, it feels like a luxury. And the fact that the battery works with other Greenworks tools makes it feel like an investment, not just a purchase.
My Bittersweet Experience: Greenworks 40V 12 Cordless String Trimmer Problem
Owning the Greenworks 40V 12 Cordless String Trimmer has been mostly positive, but like any tool, it has its quirks. Here are the main issues I faced, along with how I worked around them.
The Trimming Line Wears Out Fast
My first frustration came when trimming around thick weeds.
- Problem: The .065″ line cuts grass well but wears down quickly when it hits tougher spots like fences, rocks, or heavy weeds. I found myself replacing line more often than I expected.
- Solution: Switching to a higher-quality replacement line helped. I also learned to let the trimmer do the work instead of forcing it into heavy patches. A little patience goes a long way here.
Battery Life Feels Short on Bigger Yards
On days when I had a lot of trimming, the battery didn’t always last long enough.
- Problem: The runtime of about 30 minutes covered my smaller jobs but fell short when tackling a larger lawn or thicker growth. Stopping to recharge broke the flow of work.
- Solution: Having a second Greenworks 40V battery ready solved this. Since the same battery works with other tools in their lineup, investing in an extra pack felt worth it.
The Auto-Feed Head Isn’t Perfect
The convenience of an auto-feed is nice, but it didn’t always behave as expected.
- Problem: At times, the line didn’t advance smoothly. This left me with uneven cuts or made me stop mid-task to check.
- Solution: A quick bump on the ground usually fixed it. Keeping the spool clean also reduced jams. With some care, it worked much better.
Slight Learning Curve With Balance
At first, I felt a bit awkward with the balance, especially around narrow corners.
- Problem: The lightweight design is easy on the arms but can feel a little “floaty” until you get used to the swing.
- Solution: After a few uses, I adjusted my grip and pace. Now it feels natural, almost like guiding a broom across the yard.
Final Thought on the Problems
These issues don’t take away from the overall value of the Greenworks 40V 12 Cordless String Trimmer. They are more like small bumps on an otherwise smooth road. With simple fixes, the tool still shines as a quiet, eco-friendly, and dependable choice for regular yard work.
Alternative Option: Ryobi 40V Review
I have tested many cordless trimmers over the years. Some were cheap and weak, while others had real power. After using the Greenworks 40V for a season, I also tried the Ryobi 40V. It felt close to a gas trimmer but without the fuel mess. Both gave me clear pros and cons, so here’s how Ryobi compares in real use.
A battery says it’s charged, but it won’t power the tool
I have run into this problem more than once. With my Greenworks, the battery light showed a full charge, but the trimmer would not start. The same issue came up with the Ryobi 40V. In my case, the fix was not always simple. Sometimes it was the battery. Other times it was the tool itself.
| Feature | Greenworks 40V 12″ | Ryobi 40V |
| Power Response | Showed charge but tool failed to start | Same issue in my tests |
| Reset Options | Reseating the battery often worked | Needed a full charger reset |
| Reliability | Stable after quick fix | Worked fine after reset, but harder to solve |
| User Frustration | Low to medium | A bit higher |
Summary: Both had this issue. Greenworks was faster to fix, while Ryobi needed more effort.
Are newer 40V batteries compatible with older tools?
This was a key point for me. I had older Greenworks batteries in my garage. With Greenworks, new packs worked fine in older tools. Ryobi was different. Some of my older tools did not accept the new batteries, which was a letdown.
| Feature | Greenworks 40V 12″ | Ryobi 40V |
| Backward Compatibility | Yes, worked with my older unit | Mixed, some tools did not fit |
| Convenience | Smooth and easy | Less flexible |
| Cost Savings | Saved money by reusing old packs | Needed an extra new pack |
Summary: Greenworks gave me more freedom. Ryobi felt more locked in.
Can a dead or faulty battery be reset?
My first Greenworks battery died during a job. I reset it with a simple charger trick, and it worked again. With the Ryobi 40V, the same trick did not always help. At times the pack would not recover, and I had to wait for a replacement.
| Feature | Greenworks 40V 12″ | Ryobi 40V |
| Reset Success | Often worked | Less reliable |
| Downtime | Short | Longer at times |
| User Control | Easy fix | Sometimes needed service |
Summary: Both can fail, but I had better luck with Greenworks resets.
My Final Thoughts on Greenworks 40V 12 Cordless String Trimmer Review
If you want a light, simple tool that makes yard work less stressful, the Greenworks 40V 12 is a strong choice. It’s perfect for small to mid-sized yards and for anyone who wants to avoid gas mess and heavy machines. But if long battery life or raw cutting power is your top need, you may want to look at other options. From my own use, it made trimming feel less like a chore and more like a quick win, and that’s why I still keep it close at hand.
FAQs for Greenworks 40V 12 Cordless String Trimmer Review
How long does the Greenworks 40V 12 Cordless String Trimmer battery last?
The battery runs about 25–35 minutes on a full charge. For light trimming, it lasts longer, but thick grass may drain it faster.
Is the Greenworks 40V 12 Cordless String Trimmer good for small yards?
Yes, it works best for small to medium yards. It is light, easy to carry, and trims well around fences, trees, and garden edges.
Can the Greenworks 40V 12 Cordless String Trimmer handle tall weeds?
It can cut through tall grass and light weeds. For thick brush, it may struggle, so a more powerful trimmer could be better.
How heavy is the Greenworks 40V 12 Cordless String Trimmer?
It weighs about 9 pounds. This makes it light enough for most users to handle without arm strain during longer jobs.
Is the Greenworks 40V 12 Cordless String Trimmer easy to use?
Yes, it is very beginner-friendly. The push-button start and simple design make trimming fast and less stressful than gas models.
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