Generac iQ3800 DF
#2 in Mid-sizeFull review
A dual-fuel mid-size inverter with long run time and electric start, suited to home essentials and jobsites. RV owners will need an L5-30 adapter for the 30 A outlet.
Amazon $849$849
The Generac iQ3800 DF rates 4.0 among mid-size inverter generators; the Generac GP2500i rates 3.5 among small ones. The Generac GP2500i costs $252.20 less ($596.80 vs $849).
Generac GP2500i
#5 in SmallFull review
A small, easy-to-carry inverter for camping, tailgating and keeping a fridge and phones running in an outage. Buyers who want an RV outlet or electric start should look one size up.
Amazon $596.80$596.80
Prices were last checked October 22, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different size classes (mid-size and small), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.
| Factor weight | Generac iQ3800 DF | Generac GP2500i |
|---|---|---|
| Overall rating | 4.0/5 | 3.5/5 |
| Value 30% | 67 $0.28 per running watt | 82 $0.27 per running watt |
| Quiet 20% | 50 noise level not published (neutral score used) | 64 53 dBA at light load, maker rating |
| Run time 15% | 100 20 hours on a tank at 25% load | 40 8 hours on a tank at 25% load |
| Fuel options 10% | 70 gasoline or propane | 0 gasoline only |
| CO safety 10% | 100 shuts off when carbon monoxide builds up | 100 shuts off when carbon monoxide builds up |
| Warranty 10% | 50 3-year warranty | 50 3-year warranty |
| Starting 5% | 80 push-button electric start | 0 pull start only |
Specifications
| Generac iQ3800 DF | Generac GP2500i | |
|---|---|---|
| Output | ||
| Gasoline | 3,000 W running, 3,800 W starting | 2,200 W running, 2,500 W starting |
| Propane | 2,700 W running, 3,400 W starting | - |
| Outlets | 4 × 120 V, L5-30, USB | 2 × 120 V, USB |
| Parallel capable | Yes | Yes |
| Total harmonic distortion | under 3% | under 3% |
| Price per watt | $0.28 | $0.27 |
| Fuel and run time | ||
| Fuel | Gasoline, propane | Gasoline |
| Tank | 3.3 gal | 1 gal |
| Run time (gasoline) | 20 hr at 25% load | 8 hr at 25% load |
| Run time (propane, 20 lb tank) | 19 hr | - |
| Engine | 212 cc | 98 cc |
| Noise and safety | ||
| Rated noise (light load) | - | 53 dBA |
| CO shutoff | Yes | Yes |
| Build | ||
| Starting | Electric and recoil | Recoil (pull) |
| App | No | No |
| Wheels | Yes | No |
| Dimensions | 24.6 x 20.3 x 22.4 in | 19.7 x 11.4 x 17.9 in |
| Weight | 107 lb | 48 lb |
| Warranty | 3 years | 3 years |