How Many Watts Is 30 Amps?
30 A is 7,200 W at 240 V DC. At other common voltages — 120 V: 3,600 W. Use the calculator below for any voltage or circuit type.
Real example: a 30 A electric clothes-dryer circuit
A 30 A circuit is the classic electric clothes-dryer and RV / water-heater rating, run in 10 AWG copper. Dryers are 240 V, so 30 A delivers 7,200 W (5,760 W continuous). On a 120 V circuit the same 30 A would be 3,600 W.
30 Amps to Watts — Voltage Reference Chart
| Voltage | Power (PF 1) | Typical use |
|---|---|---|
| 12 V | 360 W | 12V DC / automotive |
| 120 V | 3,600 W | US household standard |
| 208 V | 6,240 W | 208V commercial (L-L) |
| 240 V | 7,200 W | US/EU 240V circuit |
| 480 V | 14,400 W | Industrial 3-phase (L-L) |
Wire & breaker: A 30 A circuit is normally run in 10 AWG copper. Remember the NEC 80% rule for continuous loads (3 hours+): usable power is 7,200 × 0.8 = 5,760 W at 240 V. Background: watts vs amps. Always confirm with a licensed electrician.
In practice: 30 A RV shore power
A TT-30 pedestal supplies 30 A at 120 V — 3,600 W in total, not the 7,200 W people often assume by reaching for the 240 V figure. That budget runs one roof air conditioner plus a few small loads, but not air conditioning and an electric water heater at once. On a 240 V circuit the same 30 A breaker feeds a clothes dryer at 7,200 W over 10 AWG.
Frequently Asked Questions
How many watts is 30 amps at 120V?
At 120V, 30 A delivers 30 × 120 = 3,600 watts (resistive, PF 1). For a continuous load the NEC limits this to 80%: 2,880 W. For AC with a power factor below 1, multiply by PF.
How many watts is 30 amps at 240V?
At 240V, 30 A delivers 30 × 240 = 7,200 watts; the 80% continuous limit is 5,760 W.
How many watts is a 30 amp dryer circuit at 240V?
A 30 A, 240 V dryer circuit carries 30 × 240 = 7,200 W maximum, or 5,760 W continuous. Most electric dryers draw 3,000–5,400 W, so they fit comfortably. A 30 A RV pedestal (120 V) is different — that is only 3,600 W. Reverse the math with watts to amps.