Compare Generators Side-by-Side
Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.
- Genmax GM1200i
- Yamaha EF3000iS
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
| Specification | Genmax GM1200i | Yamaha EF3000iS |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Gasoline |
| Inverter | Yes | Yes |
| Parallel capable | Yes | No |
| RV ready | No | No |
| Running watts | 1000 W | Winner: Winner: 2800 W |
| Starting watts | 1200 W | Winner: Winner: 3000 W |
| Noise (lower limit) | 58 dB | Winner: Winner: 54.5 dB |
| Weight | Winner: Winner: 25.3 lbs | 136 lbs |
| Run time @50% load | Winner: Winner: 6.5 h | Not available |
| Run time @25% load | 10 h | 18.6 h |
| Fuel tank | 0.7 gal | 3.4 gal |
| Fuel gauge | No | Yes |
| Approx. dimensions (L × W × H) | 16.5 x 9.5 x 15.7 | 26.8 x 17.5 x 21.9 |
| Electrical | ||
| Voltage (AC) | 120V 60 Hz | 120 |
| Voltage (DC) | 5V | Not available |
| GFCI outlets | No | No |
| Covered outlets | Yes | No |
| Automatic Voltage Regulation | Yes | Yes |
| THD | <1.2% % | Not available |
| Engine | ||
| Engine | 57 cc Dinking OHV 4-stroke | 171 cc Yamaha MZ175 OHV 4-stroke |
| Alternator | Not available | Not available |
| Starting system | Recoil | Recoil |
| Warranty | ||
| Warranty | 1 years | 3 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 1000 W | 2800 W |
| Starting watts | 1200 W | 3000 W |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | 6.5 h | Not available |
| Run time @25% load | 10 h | 18.6 h |
| Other | ||
| Data center | Not available | Not available |
| Indicators | true | true |
| Compliance | EPA, ANSI/PGMA G300-2023 | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Not available | Floating |
| UPC | 768494055271 | 810856030645 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 1000 | 2800 |
| Starting Watts (Gasoline) | 1200 | 3000 |
| Runtime @ 50% Load (Gasoline) | 6.5 | Not available |
| Runtime @ 25% Load (Gasoline) | 10 | 18.6 |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R) | AC outlets1x Duplex 120V 20A (5-20R)1x 120V 30A (L5-30R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | Not available | Yamaha MZ175 OHV 4-stroke |
| Engine Displacement | 57 | 171 |
| Engine Oil Type | 10W-30 | Not available |
| Runtime & fuel system | ||
| Runtime @ 25% Load (Gasoline) | 10 | 18.6 |
| Runtime @ 50% Load (Gasoline) | 6.5 | Not available |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection, CO monitoring | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | Yes |
| Included equipment | ||
| Fuel Connection Components | Funnel, tool kit, RV adapter, and parallel cables | Not available |
| Included Accessories | Funnel, tool kit, RV adapter, and parallel cables | Battery charging cables |
| Warranty & identification | ||
| Commercial Warranty | Not available | 3 |
| Additional specs | ||
| Summary | The Genmax GM1200i is a 1000-watt gasoline inverter generator built for portability and quiet operation. At 25.3 lbs, it moves easily between job sites, campsites, and storage. The 1200-watt surge capacity handles startup demands for small appliances, power tools, and sensitive electronics. | The Yamaha EF3000iS is a 3000-watt inverter generator designed for quiet operation and portability, featuring advanced technologies like Smart Throttle and Noise Block, and backed by a 3-year limited warranty. |
- Most PowerfulYamaha EF3000iS2800W running
- QuietestYamaha EF3000iS54.5 dB
- Longest RuntimeGenmax GM1200i6.5h at 50% load
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Genmax GM1200i
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Yamaha EF3000iS
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