What size generator to run an air compressor?
Air compressor (1 HP) draws about 1,600W while running and surges to 4,500W on startup. Allowing 20% headroom, size for at least 5,400W of starting capacity.
The surge is the number that matters. A generator rated to 1,600W will stall the moment the motor kicks in, because for a fraction of a second it needs 4,500W. Manufacturers advertise running watts, which is why people routinely buy one size too small.
Units that cover it
- Honda EU7000iS
7,000W starting · 56% headroom
Comfortable headroom without overpaying for capacity, has a CO shutoff sensor, runs at 58 dB.
Check price - Ryobi RYi6522
6,500W starting · 44% headroom · $999
Comfortable headroom without overpaying for capacity, has a CO shutoff sensor.
Check price - Pulsar PGX60BiSRCO
6,000W starting · 33% headroom · $1,299
Comfortable headroom without overpaying for capacity, has a CO shutoff sensor, runs on propane as well as gasoline.
Check price
Running more than one thing
Most people are not powering one appliance. Add everything you need at once and the calculator works out the real peak — your total running load plus the single largest surge, not the sum of every surge.
Size the whole load