⚡ Briggs & Stratton Generator Size Calculator
Select your appliances, enter quantities, and instantly find the correct generator wattage for your home, RV, or jobsite.
| Include | Appliance | Running Watts | Starting Watts | Qty |
|---|
| Appliance | Running Watts | Starting Watts | Category | Priority |
|---|---|---|---|---|
| Central AC (1.5 ton) | 1500 | 4500 | HVAC | High |
| Central AC (3 ton) | 3500 | 10500 | HVAC | High |
| Central AC (5 ton) | 5500 | 16500 | HVAC | High |
| Window AC (5,000 BTU) | 500 | 1500 | HVAC | Medium |
| Window AC (10,000 BTU) | 1200 | 3600 | HVAC | Medium |
| Refrigerator (Standard) | 700 | 2200 | Kitchen | High |
| Freezer (Chest) | 500 | 1500 | Kitchen | High |
| Electric Range (1 burner) | 1500 | 1500 | Kitchen | Low |
| Microwave (1000W) | 1000 | 1000 | Kitchen | Medium |
| Electric Water Heater | 4000 | 4000 | Water | Low |
| Sump Pump (1/3 HP) | 800 | 1300 | Water | High |
| Sump Pump (1/2 HP) | 1050 | 2150 | Water | High |
| Well Pump (1/2 HP) | 1000 | 2100 | Water | High |
| Well Pump (1 HP) | 2000 | 4000 | Water | High |
| Furnace Fan / Blower | 800 | 2350 | HVAC | High |
| Electric Furnace | 10000 | 10000 | HVAC | Medium |
| LED TV (55 inch) | 100 | 100 | Electronics | Low |
| Desktop Computer | 200 | 200 | Electronics | Low |
| Laptop | 50 | 50 | Electronics | Low |
| Phone / Tablet Charger | 20 | 20 | Electronics | Medium |
| LED Lighting (per bulb) | 10 | 10 | Lighting | High |
| Incandescent Bulb (100W) | 100 | 100 | Lighting | High |
| Circular Saw (7-1/4") | 1400 | 2300 | Tools | Jobsite |
| Table Saw (10") | 1800 | 4500 | Tools | Jobsite |
| Air Compressor (1 HP) | 1600 | 4500 | Tools | Jobsite |
| Air Compressor (2 HP) | 2000 | 6000 | Tools | Jobsite |
| Electric Drill (1/2") | 600 | 900 | Tools | Jobsite |
| Welder (Arc 200A) | 3000 | 3000 | Tools | Jobsite |
| RV Air Conditioner (13.5K BTU) | 1500 | 3300 | RV | High |
| RV Refrigerator | 180 | 600 | RV | High |
| Coffee Maker | 800 | 800 | Kitchen | Low |
| Washing Machine | 500 | 2300 | Laundry | Low |
| Electric Dryer | 5000 | 6750 | Laundry | Low |
| Security System | 180 | 180 | Safety | High |
| Medical Equipment (CPAP) | 30 | 30 | Medical | High |
| Model Series | Running Watts | Peak Watts | Engine CC | Fuel Tank (gal) | Runtime @ 50% | Best For |
|---|---|---|---|---|---|---|
| P2400 PowerSmart Series (Inverter) | 1700 | 2400 | 111cc | 1.0 | 8 hrs | RV, Tailgate, Camping |
| P3000 PowerSmart Series (Inverter) | 2600 | 3000 | 224cc | 1.5 | 10 hrs | RV, Small Home |
| Q6500 QuietPower Series | 5500 | 6500 | 420cc | 6.1 | 11 hrs | Home Essentials |
| Pro Series 3500 | 3000 | 3500 | 208cc | 4.0 | 9 hrs | Tailgate, Small Home |
| Pro Series 6500 | 5500 | 6500 | 420cc | 6.1 | 11 hrs | Home, Jobsite |
| Pro Series 8000 | 8000 | 10000 | 457cc | 7.9 | 11 hrs | Large Home, HVAC |
| Elite Series 7500 | 7500 | 9375 | 457cc | 7.9 | 11 hrs | Home + AC |
| Q12500 QuietPower | 10000 | 12500 | 724cc | 10.2 | 10 hrs | Whole Home |
| Home Standby 10kW | 10000 | 10000 | -- | Nat. Gas | Continuous | Whole Home Standby |
| Home Standby 20kW | 20000 | 20000 | -- | Nat. Gas | Continuous | Large Home Standby |
| Motor Type | Running Watts Example | Starting Multiplier | Peak Starting Watts | Duration |
|---|---|---|---|---|
| Capacitor Start Motor (AC, pumps) | 1000W | 2–3x | 2000–3000W | 1–3 sec |
| Split-Phase Motor (Appliances) | 800W | 3–5x | 2400–4000W | 1–2 sec |
| Universal Motor (Power Tools) | 1400W | 1.5–2x | 2100–2800W | <1 sec |
| AC Compressor (HVAC) | 3500W | 2–4x | 7000–14000W | 2–5 sec |
| Induction Motor (General) | 1200W | 2–3x | 2400–3600W | 1–3 sec |
| Resistive Load (No Motor) | Any | 1x | Same as running | N/A |
| Generator Size | 25% Load (gal/hr) | 50% Load (gal/hr) | 75% Load (gal/hr) | 100% Load (gal/hr) | 8-hr Cost @ $3.50/gal |
|---|---|---|---|---|---|
| 2000W Inverter | 0.09 | 0.13 | 0.17 | 0.23 | ~$3.64 (50% load) |
| 3500W Portable | 0.25 | 0.36 | 0.47 | 0.63 | ~$10.08 |
| 6500W Portable | 0.38 | 0.55 | 0.72 | 0.95 | ~$15.40 |
| 8000W Portable | 0.47 | 0.67 | 0.86 | 1.15 | ~$18.76 |
| 12500W Portable | 0.58 | 0.87 | 1.16 | 1.50 | ~$24.36 |
Choosing the right size of generator is a really important decision. Every device in the home requires a different amount of energy. The secret lies in counting which devices are the most important during a loss of electricity.
Adding the watts of those needs, one finds the right size for the generator. There are even special calculators for watts that help to find the ideal model based on the size of the home, fuel type, and which devices one wants to keep working.
How to Choose the Right Generator Size
Briggs and Stratton offer generators in a wide range of sizes. At the small end one finds portable inverter generators, for example the series P2500 PowerSmart, that reaches 2500 starting watts. It delivers clean and quiet energy, so it works for computers and sensitive electronics.
It also has CO-Guard technology for safety and a compact form. There are also other portable options. For instance one model reaches about 2200 starting watts and 1700 running watts and it operates at 59 decibels, which is fairly quiet for its size.
Between other portable options is a model with 8000-watt electric start and one with 5550 watts for running.
For back-up generators the sizes become much bigger. Briggs and Stratton produce units of 10 kW, 12 kW, 15 kW and 20 kW. The models of 10 kW and 12 kW, just like those of 15 kW and 20 kW, can combine with an automatic transfer switch, that covers needs and even up to two 5-ton air conditioners.
Then come the series PowerProtect, that reaches even higher levels. The model of 20 kW restores energy automatically during power outages and has standard features like low oil shutoff, high temperature shutoff, LED display, and built-in charger for the battery. At the upper end stands the PP26, a unit of 26 kW on propane or 24 kW on natural gas, that comes with a 200-amp disconnect switch.
A system of 12 kW with Symphonic Energy Management and a 200-amp automatic transfer swich costs around 10 826 dollars. That helps to imagine what the prices look like for mid-size models.
The best back-up generator depends on the priorities of the family. Some folks want energy for the whole house. Others only care that things stay comfortable and save money.
The amount of devices that must run during a power outage affects both the size and the cost.
Buying a bit bigger generator than the clear need is commonly a smart choice. When the engine ages, it naturally loses power. This way you have back-up ability sew that it lasts longer under the same load.
For businesses Briggs and Stratton also prepare commercial back-up generators, that aim to keepoperations going during power outages. Every unit passes strict tests, to ensure that it handles various conditions.
