Greenworks 40V 21" Brushless Cordless (Self-Propelled) Lawn Mower (75+ Compatible Tools), 5.0Ah Battery and Charger Included Review

Overview

The Greenworks 40V 21" Brushless Cordless Self-Propelled Lawn Mower is a battery-powered workhorse designed for suburban homeowners with medium-sized yards—think a quarter to a third of an acre. It combines the convenience of push-button starting and zero gas or oil with the muscle of a brushless motor and a self-propelled drive system, making it a strong contender for anyone looking to ditch the maintenance headaches of a gas mower without sacrificing cutting performance.

Who Should Buy This

Homeowners with 1/4 to 1/3 acre lawns – The included 5.0Ah battery delivers roughly 45–60 minutes of runtime on a single charge, which is enough to handle a standard suburban lot without stopping to recharge. If your yard pushes toward half an acre, you’ll likely need a second battery.

People who hate gas cans and small engines – No fuel mixing, no carburetor cleaning, no pull cords that snap back at your shins. This mower starts with the press of a button and runs silently enough to mow early Saturday morning without waking the neighbors.

DIY landscapers who want tool ecosystem flexibility – Greenworks’ 40V platform includes over 75 compatible tools—trimmers, blowers, chainsaws, even a snow thrower. If you already own Greenworks 40V gear, you can share batteries across the lineup.

Seniors or anyone with a hilly yard – The self-propelled variable-speed drive takes the grunt work out of mowing. You set the pace with a lever, and the mower does the heavy pushing, especially welcome on slopes or if you have knee or back issues.

Key Features Breakdown

40V 5.0Ah Battery – This is a high-capacity lithium-ion pack, not the 2.0Ah starter battery you see on cheaper models. Expect 45–60 minutes of real-world mowing, depending on grass thickness and self-propelled use. It charges in about 2 hours, so plan accordingly if you have a larger lawn.

21" Brushless Motor – Brushless motors are more efficient, quieter, and last longer than brushed alternatives. The 21-inch cutting deck strikes a good balance between maneuverability and coverage—wide enough to finish a lawn in reasonable time, narrow enough to fit through most gates.

Self-Propelled Variable Speed – The rear-wheel drive system is controlled by a bail lever and a speed dial. You can creep along for thick patches or walk briskly on open stretches. It’s not as refined as a Honda or Toro gas self-propel system, but for the price, it’s very competent.

7-Position Single-Lever Height Adjustment – A single lever adjusts cutting height from 1.5 to 4 inches. No bending over to adjust each wheel individually. This is a time-saver and a back-saver.

Push-Button Start – No pull cord, no primer bulb, no choke. Press the button, squeeze the bail, and go. It’s as close to a “just works” experience as you get in lawn care.

75+ Compatible Tools – This is the hidden value. If you buy into Greenworks’ 40V system, you can swap the same battery between a leaf blower, string trimmer, hedge trimmer, and more. Over time, this saves you money and storage space.

Pros

• Instant start, zero hassle – Push a button and mow. No gas, no oil, no fumes. It’s genuinely satisfying.
• Quiet operation – At around 75 decibels, it’s whisper-quiet compared to a gas mower. You can hold a conversation while mowing.
• Solid battery life for the price – The 5.0Ah battery handles a typical 1/4-acre lawn with juice to spare. Greenworks’ battery management also prevents over-discharge, extending pack life.
• Good cut quality – The brushless motor keeps blade speed consistent even in thick grass. It mulches well, bags decently, and the side discharge is functional.
• Tool ecosystem bonus – If you already own Greenworks 40V tools, you’re buying into a shared battery system. If not, this is a great entry point.
• Self-propelled actually works – The variable-speed drive is responsive and helps on inclines. It’s not a gimmick—it saves real effort.

Cons

• Not for large lawns – If you have half an acre or more, you’ll need a second battery or a gas mower. The 5.0Ah pack won’t finish a big yard in one go.
• Self-propelled drive can be jerky – The engagement is a bit binary. It takes a few mows to dial in the speed setting that feels natural. Some users report it lurching on uneven terrain.
• Plastic deck durability concerns – The deck is high-impact plastic, which is light and rust-proof, but it won’t take a rock hit as well as steel. Over years of use, the deck can crack if you’re careless with obstacles.
• Battery and charger are heavy – The 5.0Ah battery weighs about 3.5 pounds, and the charger is bulky. Hauling them from garage to shed isn’t a dealbreaker, but it’s worth noting.

Bottom Line

The Greenworks 40V 21" Self-Propelled Mower is a smart buy for the suburban homeowner who wants to cut the cord—both literally and figuratively—from gas mowers. It delivers reliable starting, good cut quality, and genuine self-propelled assistance at a price that undercuts most comparable gas models. It’s not built for commercial use or sprawling acreage, but for a quarter-acre lot with some hills, it’s one of the best battery-powered options under $400. If you’re already in the Greenworks 40V ecosystem, this is a no-brainer upgrade. If you’re new to battery mowing, this is a great place to start.

Frequently Asked Questions

How long does the battery actually last?
In real-world use with the self-propelled engaged, expect 40–50 minutes of cutting. If you disengage the drive and walk at a steady pace, you can push it to about 60 minutes. Thick, damp grass will drain it faster. The charger takes about 2 hours to fully recharge the 5.0Ah pack.

Can I use a larger battery with this mower?
Yes. Greenworks sells 4.0Ah, 5.0Ah, and 8.0Ah batteries that all fit this mower. The 8.0Ah pack will give you longer runtime but adds weight and makes the mower feel a bit nose-heavy. If you have a larger lawn, the 8.0Ah is a worthwhile upgrade.

Does it really mulch and bag well?
Mulching performance is good for a battery mower—the brushless motor keeps blade speed up