The Greenworks AiMowbot C30Z is the better robot lawn mower overall, rated 4.2 to 4.0. The Greenworks AiMowbot C30Z leads on value. The Greenworks AiMowbot C20Z costs $300 less ($1,299.99 vs $1,599.99).
For flat-to-moderate lawns up to three-quarters of an acre, from owners who want a mainstream brand’s warranty on a wire-free RTK mower. Hilly yards need an AWD model.
Amazon $1,599.99 Greenworks $1,599.99For flat-to-moderate half-acre lawns where a mainstream brand and app-set cutting height matter. It costs more than rivals with similar specs.
Amazon $1,299.99Prices were last checked October 21, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Each factor is scored 0-100 against the same fixed reference points for every 1/4 to 1 acre robot lawn mower; a clear win is highlighted. How we rank explains each one.
| Factor weight | Greenworks AiMowbot C30Z | Greenworks AiMowbot C20Z |
|---|---|---|
| Overall rating | 4.2/5 | 4.0/5 |
| Value 30% | 86 $2,130 per rated acre | 76 $2,600 per rated acre |
| Navigation 20% | 80 RTK + vision, no boundary wire | 80 RTK + vision, no boundary wire |
| Slopes 20% | 36 45% (24°) slopes | 36 45% (24°) slopes |
| Features 15% | 100 7 of 7 | 100 5 of 5 |
| Warranty 10% | 67 3-year warranty | 67 3-year warranty |
| Noise 5% | 100 54 dB(A) rated | 100 54 dB(A) rated |
| Greenworks AiMowbot C30Z | Greenworks AiMowbot C20Z | |
|---|---|---|
| Coverage | ||
| Lawn size (rated) | 0.75 acres (32,700 sq ft) | 0.5 acres (21,800 sq ft) |
| Max slope | 45% (24°) | 45% (24°) |
| All-wheel drive | No | No |
| Charge time | 50 min | - |
| Navigation | ||
| Navigation | RTK + vision | RTK + vision |
| Boundary wire needed | No | No |
| RTK station | Included | - |
| Obstacle avoidance | AI cameras + ToF camera + night-vision sensors (200+ object types) | AI cameras + ToF camera + night-vision sensors (200+ object types) |
| Multiple zones | Yes | Yes |
| No-go zones | Yes | Yes |
| Cutting | ||
| Cutting width | 8 in (203 mm) | 7.9 in (200 mm) |
| Cutting height | 0.8–3.5 in | 0.8–3.5 in |
| Height adjustment | In the app | In the app |
| Edge mowing | Edge mowing to within 4 in | Edge mowing to within 4 in |
| Smart features | ||
| Connectivity | Wi-Fi, Bluetooth, 4G | - |
| Anti-theft | Alarm when the mower leaves its area (requires 4G and anti-theft activation) | - |
| Build | ||
| Noise (rated) | 54 dB(A) | 54 dB(A) |
| Water resistance | IPX6 | IPX6 |
| Warranty | 3 years | 3 years |
