Compare Mowers
List prices are the manufacturer’s published figures, re-checked daily; they exclude tax, freight and dealer setup.
A side-by-side reference of each model's stated specifications. MowerFacts doesn’t give opinions: where a published, spec-derived rule can separate machines we mark a Data Pick and show the rule; here, read the values and decide what fits your needs.
Best suited for
What each model is built for, from its duty class and key specs. This is a neutral reference — MowerFacts does not rank one model above another.
- Ryobi 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… — residential: typical home lawns; 21-inch deck; battery (no fuel or engine maintenance)
- Ryobi 18V ONE+ HP Brushless 16 in Push Mower — residential: typical home lawns; 16-inch deck; battery (no fuel or engine maintenance)
What’s different? The 5 differences that matter most, from the published figures.
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… lists at $849; 18V ONE+ HP Brushless 16 in Push Mower lists at $229, a $620 difference. List price is the maker's own figure before tax, freight and dealer setup. Dealers set the final price.
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… runs on a 40 V battery; 18V ONE+ HP Brushless 16 in Push Mower runs on a 18 V battery, a 22 V difference. Battery voltage names the platform. Run time depends on the pack's capacity in amp-hours and on the cutting load.
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… weighs 79 lbs (35.7 kg); 18V ONE+ HP Brushless 16 in Push Mower weighs 34 lbs (15.6 kg), a 44 lbs difference. Operating weight bears on trailer payload, ramps and soft turf. On its own it says nothing about build quality. What 40V HP Brushless 21 in Self-Propelled All-Wheel Drive…'s weight means for a trailer ›
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… has a 21 in (533 mm) deck; 18V ONE+ HP Brushless 16 in Push Mower has a 16 in (406 mm) deck, a 5 in difference. Deck width sets how much grass each pass covers. Mowing time also depends on ground speed, turns and obstacles, so a wider deck alone does not fix the job's length. Time both decks on your own lawn ›
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… carries a 5-year warranty; 18V ONE+ HP Brushless 16 in Push Mower carries a 3-year warranty, a 2 years difference. Warranty length is the maker's published term. Conditions and commercial-use limits differ between makers.
2 more differences, what isn’t comparable
Other verified differences
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… has Mulching, Bagging, and Side Discharge discharge; 18V ONE+ HP Brushless 16 in Push Mower has Mulching and Bagging discharge.
- 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… cuts from 1 in (25 mm) to 4 in (102 mm); 18V ONE+ HP Brushless 16 in Push Mower cuts from 1.5 in (38 mm) to 4 in (102 mm).
Not comparable
- Bagger Capacity: not published for 18V ONE+ HP Brushless 16 in Push Mower.
- Deck Material: not published for 40V HP Brushless 21 in Self-Propelled All-Wheel Drive….
Verified means each manufacturer publishes the figure. A bigger number is only a bigger number; nothing here says which machine is better. The full specification table is below.
Which is faster on your property? › Measure your lawn once and MowerFacts times all 2 against it.
| Spec | 40V HP Brushless 21 in Self-Propelled All-Wheel Drive… Ryobi · Push / Walk-Behind |
18V ONE+ HP Brushless 16 in Push Mower Ryobi · Push / Walk-Behind |
|---|---|---|
| List price | $849 | $229 |
| Engine | ||
| Power Source | battery | battery |
| Fuel Type | Battery / Electric | Battery / Electric |
| Electrical | ||
| Voltage | 40 V | 18 V |
| Deck | ||
| Cutting Width | 21 in (533 mm) | 16 in (406 mm) |
| Min Cut Height | 1 in (25 mm) | 1.5 in (38 mm) |
| Max Cut Height | 4 in (102 mm) | 4 in (102 mm) |
| Deck Material | — | ABS Plastic |
| Discharge | Mulching, Bagging, and Side Discharge | Mulching and Bagging |
| Drive | ||
| Drive Type | All-Wheel Drive | Push |
| Dimensions | ||
| Weight | 79 lbs (35.7 kg) | 34 lbs (15.6 kg) |
| General | ||
| Warranty | 5 yr | 3 yr |
| Bagger Capacity | 2 bu (70.5 L) | — |
40V HP Brushless 21 in Self-Propelled All-Wheel Drive…: Specs verified against the manufacturer spec sheet on Jun 6, 2026 — ryobitools.com.
18V ONE+ HP Brushless 16 in Push Mower: Specs verified against the manufacturer spec sheet on Jun 6, 2026 — ryobitools.com.
Independent reference database. Specs compiled from manufacturer sources and normalized for comparison; verify with the manufacturer or dealer before purchase.