What Size Generator Do You Need for a Home Office?
By the Generator Size Calculator Team · Updated · 6 min read
Quick answer: Office electronics are light. Honda lists a computer at 150 watts, a printer at 100, a modem at 25 and a TV at 300. A desk setup alone is under 300 watts, so a 1,000 to 2,000-watt inverter generator is plenty. Add a refrigerator (700 running, 2,200 starting) and a 3,000-watt inverter covers the whole list. Inverters give the cleanest power for sensitive electronics.
Watts for office equipment
| Equipment | Running watts | Starting watts |
|---|---|---|
| Computer | 150 | 150 |
| Printer | 100 | 100 |
| Modem | 25 | 25 |
| Color television | 300 | 300 |
| Refrigerator or freezer | 700 | 2,200 |
Lights are extra: add the watts printed on each bulb. LED bulbs use far less than old incandescents. A desktop, monitor, modem and router with a few LED lights can be well under 400 watts.
Which generator size to choose
| Setup | Generator |
|---|---|
| Laptop, modem, router, lights | 1,000 W inverter |
| Desktop, monitor, printer, modem, lights | 1,000 to 2,000 W inverter |
| Add a refrigerator and a TV | 3,000 W inverter |
Our estimates keep the running load under 80% of rating. For very short outages, a portable power station can run a laptop and a router quietly with no fuel.
Example: desk, fridge and TV
| Load | Running watts |
|---|---|
| Refrigerator | 700 |
| Television | 300 |
| Computer | 150 |
| Printer | 100 |
| Modem | 25 |
| Running total | 1,275 |
With the fridge compressor starting, the peak is about 1,275 plus 1,500, or 2,775 watts. A 3,000-watt generator carries 1,275 running watts well under its 80% mark (2,400 watts), and its approximate 3,750-watt starting capacity covers the peak. Lights add a little more.
List your own equipment for an exact size.
Why clean power matters
Computers and routers have sensitive circuit boards. Honda says inverter generators give the cleanest power for sensitive electronics, and manufacturers typically quote under 3% total harmonic distortion. A surge protector adds protection. Read inverter vs conventional generators and use the inverter generator calculator.
Internet also needs power upstream: if your internet goes down in an outage, a generator will not bring it back. A phone hotspot is a good backup.
Run the generator outdoors, at least 20 feet from doors, windows and vents. Never in a garage or shed, even with the door open. See how far a generator should be from your house.
Frequently asked questions
How many watts does a computer use?
Honda lists a computer at about 150 watts, a printer at 100 and a modem at 25, though gaming desktops and extra monitors use more.
What size generator do I need to work from home?
For a laptop, modem and lights, a 1,000-watt inverter is plenty. Add a fridge and a TV and a 3,000-watt inverter is a comfortable size.
Is an inverter generator better for computers?
Yes. Inverters usually produce cleaner power, which suits sensitive electronics. See the inverter vs conventional comparison.
Can a power station replace a generator?
For a laptop, router and lights over a few hours, often yes. For a fridge for days, a generator is usually more practical.
Will a generator keep my internet working?
Only if the internet itself is up. A generator powers your modem and router, but cannot fix an outage on your provider's network.
Related calculators
Sources: Running and starting watts from the Honda generator wattage guide (computer, printer, modem, television, refrigerator); inverter power quality notes from Honda and Renogy. Generator sizes apply the 80% running rule and a starting capacity about 25% above rating.