Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah Review: The Gas-Killer We’ve Been Waiting For?

For years, the Saturday morning ritual was the same: the trip to the garage, the hunt for the gas can, the inevitable spill of smelly fuel, and the frustrating, shoulder-straining pulls on a stubborn starter cord. The roar of the engine would shatter the neighborhood peace, and the fumes would linger long after the job was done. We, like many homeowners, had grown weary of the maintenance, the noise, and the environmental toll of our old gas-powered lawn mower. We longed for a simpler, cleaner, and quieter solution, but we were skeptical. Early battery-powered mowers often felt like toys—underpowered, with flimsy plastic bodies and batteries that died before the back lawn was even half-finished. The fear was trading one set of frustrations for another, sacrificing raw cutting power for convenience. That’s the conundrum that led us to test the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah, a machine that promises gas-like performance without any of the gas-related headaches.

What to Consider Before Buying a Walk-Behind Lawn Mower

A walk-behind lawn mower is more than just an item; it’s a key solution for maintaining a healthy, beautiful lawn and preserving your weekend sanity. For most homeowners, it represents the perfect balance of control, maneuverability, and cutting power. Unlike large riding mowers, a walk-behind can navigate tight corners, landscaped beds, and sloped terrain with ease. The primary benefit of investing in a high-quality model is the time and effort saved. A powerful, reliable mower turns a dreaded chore into a satisfying task, delivering a clean, uniform cut that promotes grass health and boosts your home’s curb appeal. A great mower simplifies yard work, eliminating the struggles of uneven cuts, constant maintenance, and equipment that fails when you need it most.

The ideal customer for a high-performance cordless walk-behind mower, like the Greenworks 80V model, is a homeowner with a small to medium-sized yard (typically up to a half-acre) who values convenience, low maintenance, and quiet operation. This user is tired of the hassles of gas engines—the mixing of fuel and oil, the tune-ups, the pull-starts, and the emissions. They want a powerful machine they can start with the push of a button and store easily. Conversely, this type of mower might not be suitable for those with multiple acres of land, where the runtime of even the best batteries would be a limiting factor. Likewise, commercial landscapers who require all-day, non-stop operation would likely still lean towards professional-grade gas mowers. For those with very small, flat lawns, a manual reel mower could be a simpler, more affordable alternative.

Before investing, consider these crucial points in detail:

• Dimensions & Space: A mower can take up a significant footprint in a garage or shed. Look for models with smart storage solutions. The Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah features EZ Fold aluminum handles that allow it to be stored vertically, reducing its storage footprint by up to 70%—a game-changer for anyone with limited space.
• Capacity/Performance: This is the heart of the mower. For cordless models, voltage (V) is a key indicator of power. An 80V system is at the high end, providing torque comparable to gas engines. Also consider the battery capacity (Ah), which determines runtime, and the cutting width (deck size), which impacts how many passes you’ll need to make. A 21-inch deck is a great all-around size for balancing speed and maneuverability.
• Materials & Durability: The mower deck is critical. Many budget electric mowers use plastic or composite decks to save weight and cost, but these can crack and are less rigid. A durable steel deck, like the one on this Greenworks model, offers superior longevity and a more stable cutting platform, ensuring it can handle the bumps and scrapes of regular use for years to come.
• Ease of Use & Maintenance: The promise of battery power is simplicity. Look for features like a single-lever height adjustment, which allows you to change the cutting height of all four wheels simultaneously, instead of fumbling with individual levers. True long-term value comes from the near-elimination of maintenance: no oil changes, no spark plugs, no air filters, and no winterizing the fuel system.

Making the right choice means aligning the mower’s features with your specific lawn care needs and priorities.

While the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah is an excellent choice, it’s always wise to see how it stacks up against the competition. For a broader look at all the top models, we highly recommend checking out our complete, in-depth guide:

First Impressions: A Robust Build That Inspires Confidence

Unboxing the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah immediately set it apart from lesser battery-powered mowers we’ve tested. There was no sense of cheap plastic or flimsy components. The first thing we noticed was the weight and solidity of the 21-inch steel deck. At 68.3 pounds, it has a reassuring heft that speaks to its durability, a feeling echoed by several users who noted it feels “robust and powerful.” Assembly was refreshingly simple and took less than 15 minutes, requiring no tools beyond a pocket knife to open the box. The EZ Fold aluminum handles snap into place securely, and the whole process is intuitive. We were mindful of a few isolated user reports of malformed bolts for the folding handle, but our unit came together flawlessly, with all hardware fitting perfectly. Sliding the massive 80V 4.0Ah battery into its compartment with a satisfying click, the mower felt balanced and ready for action. The single-lever height adjustment moved smoothly through its seven positions, a premium touch that we appreciate. From the very first impression, this machine felt less like a compromise and more like a serious piece of lawn equipment ready to challenge its gas-guzzling cousins. You can see its full feature set and user reviews to get a better sense of its build quality.

Performance Deep Dive: Putting the Greenworks 80V Mower to the Test

A mower’s true worth is proven on the lawn, not in the spec sheet. We put the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah through a series of real-world tests on a suburban lot with varied conditions—from thick, damp grass to leaf-covered sections and slight inclines. Our goal was to push it to its limits and see if the battery-powered dream of effortless, powerful mowing has finally become a reality.

The 80V Powerhouse: Taming Overgrown Lawns and Wet Grass

The single biggest question with any battery mower is: does it have the guts? In this case, the answer is an emphatic yes. The 80V brushless motor is the star of the show, delivering a stunning amount of torque that rivals, and in some cases surpasses, a comparable 140-160cc gas engine. To test this, we intentionally let a section of our lawn become overgrown for two weeks, resulting in thick, damp grass nearly a foot high in some spots. We set the deck to a medium height (position 4) and pushed forward, bracing for the familiar bogging sound of an engine struggling. It never came. Instead, we witnessed the mower’s intelligent power-sensing feature in action. As it hit the dense patches, the blade speed audibly kicked into a higher gear, chewing through the thick grass without hesitation and flinging the clippings into the bag with force. One user perfectly described it as a “beast” that “worked like a dream” on their own overgrown yard, a sentiment we wholeheartedly confirm.

This power isn’t just for extreme situations. It translates into a cleaner, healthier cut in normal conditions. The high-lift blade creates a powerful vortex under the steel deck, pulling grass blades upright for a precise, even cut. We also tested its leaf-pickup capabilities in the fall, and it performed magnificently. As one owner reported, it “vacuumed up leaves as I cut, leaving the yard nearly spotless.” It essentially combines mowing and leaf cleanup into a single pass, saving an incredible amount of time and effort. The sheer power of this high-voltage system is what finally allows homeowners to switch from gas without feeling like they’ve made a downgrade.

Battery Life and The 80V Ecosystem: Runtime Realities

Power is useless without adequate runtime. Greenworks claims the included 4.0Ah battery can handle lawns up to 1/2 acre. In our testing on a 1/4 acre lot with moderately thick grass, this claim proved to be quite accurate. We completed the entire lawn, front and back, in about 40 minutes, and the battery still showed one of four indicator lights remaining. This aligns perfectly with a user who mowed their 1/4-1/2 acre hilly lot and got 40 minutes from the first battery. The mower’s efficiency is remarkable; runtime will vary based on grass thickness and height, but for the target user, one battery is often sufficient.

However, for those with properties closer to the half-acre mark or who prefer to mulch instead of bag (which requires more power), having a second battery is highly recommended. The included rapid charger is another key component, bringing a fully depleted 4.0Ah battery back to 100% in just under an hour by our stopwatch, though some users report times as fast as 30 minutes. This means with two batteries, you can achieve continuous runtime—mow with one while the other charges. Furthermore, this battery is the key to an entire ecosystem of over 75 other Greenworks 80V tools, from string trimmers and leaf blowers to chainsaws. This creates incredible value; once you’ve invested in the system, you can purchase “tool-only” versions of other products at a much lower cost, building a complete, high-performance, gas-free yard care arsenal.

Ergonomics, Versatility, and Quiet Operation

Beyond raw power, the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah is simply a pleasure to use. The push-button start is instantaneous. There is no cord to pull, no choke to fiddle with. The single-lever height adjustment is a massive quality-of-life improvement, allowing for on-the-fly changes with one hand. While it is a push mower and not self-propelled, its 68-pound weight is well-balanced, and it rolls smoothly on its large wheels. For a flat or moderately sloped yard, we found it easy to maneuver and didn’t miss the complexity and extra weight of a self-propel system.

The 4-in-1 system (mulch, bag, side discharge, turbo leaf pickup) adds a layer of versatility that adapts to any season or lawn condition. The mulch plug and side-discharge chute are easy to install, and the large-capacity bag attaches and detaches smoothly. Perhaps the most striking feature during operation is the sound—or lack thereof. It operates at a low hum, about as loud as a large box fan. You can easily hold a conversation while it’s running. One owner loved how quiet it was, joking they didn’t think their neighbors knew they were doing yard work. This is a profound benefit, not just for your own ears, but for maintaining neighborhood peace, especially for those early morning or late evening mows, which are made possible by the surprisingly bright LED headlights. It’s a thoughtful feature that truly sets it apart.

What Other Users Are Saying

Scouring user feedback reveals a largely enthusiastic consensus that mirrors our own findings. The overwhelming majority of owners are, in the words of one, “blown away.” A particularly compelling story comes from a user whose grass had grown to a foot high; they set up the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah in 15 minutes and it “worked like a beast,” leveling the overgrown lawn without any prior weed-whacking. This raw power is the most frequently praised attribute.

Many converts from gas mowers celebrate the freedom from maintenance. One user, after 10 years with gas, praised the lack of “gas/oil/fumes/heavy mowers” and found the Greenworks to be lighter and even better in heavy or wet grass. The quiet operation is another universally loved feature, with one owner calling it “AMAZING!” and loving the “Tyson like punch” it packs in a quiet package.

However, the experience isn’t universally perfect. The most consistent negative feedback revolves around two areas: quality control and customer service. One user shared a frustrating story of receiving a unit with a malformed bolt for the folding handle, which required a DIY fix. Another owner had a tab on the battery cover break and was allegedly told by customer service that the part was not sold, leaving them feeling stranded. While these appear to be isolated incidents, they highlight a potential gap between the product’s excellent engineering and the company’s support infrastructure that prospective buyers should be aware of.

How Does the Greenworks 80V Mower Compare to the Alternatives?

While the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah is a formidable machine, it exists in a diverse market. Understanding its place requires looking at a few distinct alternatives that cater to different needs and priorities.

1. BILT HARD 16 Inch Electric Dethatcher Scarifier

It’s important to clarify that this is not a lawn mower, but a specialized lawn health tool. The BILT HARD Dethatcher is designed to remove the layer of dead grass and debris (thatch) from your lawn, which improves air, water, and nutrient penetration to the soil. While the Greenworks mower cuts the grass, this tool renovates the lawn at its roots. A homeowner might choose this *in addition* to a mower, not as a replacement. If your primary concern is not just cutting but actively improving the health and thickness of your turf, a dethatcher like this is an essential part of a complete lawn care regimen.

2. LiTHELi 17 Inch Cordless Lawn Mower 4.0Ah

The LiTHELi mower is a more direct competitor, but it targets a different segment of the market. With its smaller 17-inch cutting deck and a dual 20V (totaling 40V) power system, it’s best suited for smaller, simpler yards. It’s lighter, more compact, and generally more affordable than the Greenworks 80V model. A user with a small townhouse lawn or limited storage space who doesn’t need to tackle exceptionally thick or tall grass would find the LiTHELi to be a perfectly adequate and budget-friendly choice. However, for larger properties or more demanding conditions, its power and cutting width would feel insufficient compared to the robust 80V, 21-inch Greenworks.

3. Sun Joe Cordless Push Reel Lawn Mower 15

The Sun Joe Reel Mower represents a completely different philosophy of lawn care. This is a manual, human-powered machine that uses a spinning cylinder of blades to snip grass like scissors, providing a famously clean cut. It is silent, emission-free, and requires virtually no maintenance besides blade sharpening. This is the ideal choice for the eco-purist with a small, flat, and well-maintained lawn. It’s not suitable for tall grass, weeds, or bumpy terrain. The Greenworks offers immense power and convenience for a much wider range of lawn types, whereas the Sun Joe offers simplicity and a workout for a very specific, niche user.

The Final Verdict: A True Gas Mower Replacement

After extensive testing and analysis, we can confidently say that the Greenworks 80V 21″ Brushless Cordless Push Lawn Mower 4.0Ah is a triumph of battery-powered engineering. It successfully closes the performance gap that for so long kept discerning homeowners tethered to their gas mowers. Its immense power, durable steel deck construction, and thoughtful design features like vertical storage and a single-lever height adjust create a user experience that is not just convenient, but genuinely superior for most residential applications. It’s quiet, powerful, and requires virtually zero maintenance.

While we acknowledge the potential for isolated quality control issues and the mixed reviews of customer service, the product itself is outstanding. For any homeowner with up to a half-acre of land who is ready to end the noise, fumes, and frustration of gas-powered mowing without sacrificing an ounce of cutting performance, this machine is an absolute top contender. It’s an investment in a simpler, cleaner, and more enjoyable lawn care routine. If you’re ready to make the switch and experience the future of mowing, we highly recommend you check the latest price and availability on this exceptional mower.