Greenworks 80V 21" Brushless Cordless (S vs Electric Lawn Mower, Self-propelled Lawn
Quick Verdict
For most homeowners with medium to large lawns, the Greenworks 80V 21" model is the stronger choice. It offers higher voltage, better cut quality, and a much higher user satisfaction rating. The 40V (2x20V) self-propelled mower is significantly cheaper and may suit smaller yards or tighter budgets, but its lower rating and less powerful system make it a compromise.
Side-by-Side
| Feature | Greenworks 80V 21" | 40V (2x20V) 18" |
|---|---|---|
| Price | $559.99 | $349.99 |
| Voltage | 80V | 40V (two 20V batteries in series) |
| Cut Width | 21 inches | 18 inches |
| Self-Propelled | Yes | Yes |
| User Rating | 4.4/5 (1,696 reviews) | 3.7/5 (228 reviews) |
| Best Yard Size | Up to 1/2 acre | Up to 1/4 acre |
Where Greenworks Wins
The Greenworks 80V system delivers more power and runtime, making it better equipped for thicker grass and larger lawns. The 21-inch cutting deck reduces mowing time compared to the 18-inch deck. With nearly 1,700 reviews and a 4.4 average, users consistently report reliable performance, good battery life, and even cuts. The higher voltage also means less torque drop under load, so it handles slopes and damp grass more effectively. For anyone mowing more than a quarter acre, the Greenworks is the more capable machine.
Where the 40V Mower Wins
The 40V (2x20V) model costs $210 less, which is a meaningful saving for budget-conscious buyers. Its 18-inch deck is lighter and more maneuverable in tight spaces, flower beds, or small fenced yards. It also uses common 20V batteries that may be shared with other tools in the same brand family. For a small, flat lawn under 0.25 acres, the lower price and lighter weight make it a practical, no-frills option. The self-propelled drive is a useful feature at this price point.
Which Should You Buy
Choose the Greenworks 80V if:
- Your lawn is 0.25–0.5 acres
- You have thick, tall, or damp grass
- You want a proven mower with strong reviews
- You prefer fewer passes per mow (21" vs 18" deck)
- Budget allows $559.99
Choose the 40V (2x20V) if:
- Your lawn is under 0.25 acres
- You need to save $210
- You value lighter weight and easier storage
- You already own compatible 20V batteries
- You don’t mind the lower user rating and smaller deck
In summary: the Greenworks wins on power, cut width, and reliability. The 40V model wins on price and agility for small spaces. Match the mower to your yard size and grass conditions.