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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 GM3300i
  • Cat RP5500
  • Model GM3300i
    Model GM3300i

    Genmax 3,000W Gas Generator

    3000W
    Running
    62 dB
    Noise
    View details
  • Model RP5500
    Model RP5500

    Cat 5,500W Gas Generator

    5500W
    Running
    0 dB
    Noise
    View details
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).
Generator Specifications Comparison
SpecificationGenmax GM3300iCat RP5500
General
Product type
Generator
Generator
Fuel
Gasoline
Gasoline
InverterYesNo
Parallel capableYesNo
RV readyYesNo
Running watts
3000 W
Winner: Winner: 5500 W
Starting watts
3300 W
Winner: Winner: 6875 W
Noise (lower limit)
Winner: Winner: 62 dB
0 dB
Weight
Winner: Winner: 47.4 lbs
178 lbs
Run time @50% load
4.5 h
Winner: Winner: 15 h
Run time @25% load
6 h
Not available
Fuel tank
1 gal
7.9 gal
Fuel gaugeNoYes
Approx. dimensions (L × W × H)
18.9 x 11.4 x 17.3
32.9 x 27.4 x 24.7
Electrical
Voltage (AC)
120
120/240
Voltage (DC)
5
Not available
GFCI outletsNoYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
Not available
Not available
Engine
Engine
145 cc Dinking OHV 4-stroke
300 cc OHV 4-stroke
Alternator
Not available
Not available
Starting system
Recoil
Recoil
Warranty
Warranty
1 years
2 years
Power by fuel
GasolineNot availableNot available
Running watts
3000 W
5500 W
Starting watts
3300 W
6875 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
4.5 h
15 h
Run time @25% load
6 h
Not available
Other
Data center
Not available
Not available
Indicators
true
false
Compliance
EPA, ANSI/PGMA G300-2023
CARB, EPA
Security
Not available
Not available
Spark arrestorYesYes
Neutral
Floating
Not available
UPC
768494056087
815683020036
Core / High-priority specs
Running Watts (Gasoline)
3000
5500
Starting Watts (Gasoline)
3300
6875
Runtime @ 50% Load (Gasoline)
4.5
15
Runtime @ 25% Load (Gasoline)
6
Not available
AC Outlet Types
1x Duplex 120V 20A (5-20R) 1x 120V 30A (TT-30R)
2x Duplex 120V 20A (5-20R) GFCI, 1x 120/240V 30A (L14-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
Dinking OHV 4-stroke
OHV 4-stroke
Engine Displacement
145
300
Engine Oil Type
10W-30
SAE 30 or 10W-30
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
6
Not available
Runtime @ 50% Load (Gasoline)
4.5
15
Safety & compliance
Overload Protection System
Low oil and overload protection, CO monitoring
Low oil and overload protection
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringYesNo
Included equipment
Included Accessories
Funnel and tool kit
Oil, funnel, tool kit, and wheel kit
Warranty & identification
Part Number
GE-3300A
502-3686
Additional specs
Summary
The Genmax GM3300i is a 3000-watt gasoline inverter generator built for portability and clean power. At 47.4 lbs, it moves easily between campsites, job sites, and homes. The 3300-watt peak output handles startup surges on power tools and appliances, while the inverter technology protects laptops and phones from voltage spikes.
The Cat RP5500 is a 5500-watt gasoline generator built for homeowners, contractors, and outdoor enthusiasts who need reliable backup power without the complexity of larger units. This wattage tier handles most household circuits simultaneously, meaning you can run a refrigerator, well pump, and power tools at the same time, but not your entire home's air conditioning system. The 6875-watt peak capacity gives it the muscle to start high-inrush devices like compressors and sump pumps without stalling. Because the RP5500 runs on gasoline, fuel is available at any gas station, eliminating the supply chain friction of propane or diesel models. The 7.9-gallon tank paired with 15-hour runtime at half load means you refuel roughly once per day under typical use, not every few hours.
  • Most Powerful
    Cat RP5500
    5500W running
  • Quietest
    Genmax GM3300i
    62 dB
  • Longest Runtime
    Cat RP5500
    15h at 50% load
Where to buy
Prices can change. We update these automatically.
Genmax GM3300i
Store links
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Cat RP5500
Store links
No links yet.
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