How do I convert amps to watts?
Multiply amps by volts for DC. For AC, multiply by voltage and power factor; balanced three-phase also uses the square root of three.
Electrical power calculator
Amps to Watts Calculator
Convert amps to watts for DC, single-phase AC, and three-phase circuits using voltage and power factor.
Interactive calculator
Amps to Watts Calculator
Result
1200.00 W
W = A x V
Live electrical power flow
DC values update as you type.
Quick answers
Amps to Watts Calculator: quick answers
Get concise answers to the most common amps to watts calculator questions before reviewing the formulas, examples, and detailed guidance below.
What is the DC amps to watts formula?
Watts equal amps multiplied by volts.
Why does power factor matter?
It converts apparent AC power into real power, so it changes the watt result.
Definition
What does an amps-to-watts calculator do?
It converts measured or expected current into real electrical power so you can compare load demand across common circuit types.
Current
Amperes measure the flow of electric charge.
Voltage
Volts provide the electrical potential behind the current.
Real power
Watts measure the useful power consumed or delivered.
Formula
Amps to watts formulas
Select the relationship that matches the supply and load.
DC
W = A x V
Direct-current power equals current multiplied by voltage.
Single-phase AC
W = A x V x PF
Power factor adjusts apparent power to real power.
Three-phase AC
W = sqrt(3) x A x V x PF
Use line voltage for a balanced three-phase system.
How to use
Calculate watts in five steps
Use a nameplate or measured values whenever possible.
- 1. Select DC, single-phase AC, or three-phase AC.
- 2. Enter current in amperes and the operating voltage.
- 3. Enter power factor for AC equipment.
- 4. Review the watt result and formula.
- 5. Validate cable, protection, installation, and code requirements separately.
Solved examples
15 amps-to-watts examples
Five beginner, five intermediate, and five advanced scenarios.
Beginner examples
Beginner
10 A at 12 V DC
120 W
Beginner
5 A at 24 V DC
120 W
Beginner
10 A at 120 V DC
1200 W
Beginner
8 A at 230 V, PF 1
1840 W
Beginner
15 A at 120 V, PF 1
1800 W
Intermediate examples
Intermediate
10 A at 230 V, PF 0.8
1840 W
Intermediate
16 A at 240 V, PF 0.9
3456 W
Intermediate
20 A at 400 V 3-phase, PF 0.85
11.78 kW
Intermediate
32 A at 415 V 3-phase, PF 0.9
20.70 kW
Intermediate
25 A at 480 V 3-phase, PF 0.88
18.29 kW
Advanced examples
Advanced
63 A at 400 V 3-phase, PF 0.86
37.54 kW
Advanced
100 A at 415 V 3-phase, PF 0.9
64.69 kW
Advanced
125 A at 480 V 3-phase, PF 0.92
91.86 kW
Advanced
150 A at 48 V DC
7.20 kW
Advanced
80 A at 240 V, PF 0.95
18.24 kW
Conversion table
Amps to watts reference table
120 V and 230 V values use DC or PF 1. The three-phase column uses 400 V and PF 0.85.
| Current | 120 V | 230 V | 400 V 3-phase |
|---|---|---|---|
| 1 A | 120 W | 230 W | 588.9 W |
| 5 A | 600 W | 1150 W | 2.94 kW |
| 10 A | 1200 W | 2300 W | 5.89 kW |
| 16 A | 1920 W | 3680 W | 9.42 kW |
| 20 A | 2400 W | 4600 W | 11.78 kW |
| 32 A | 3840 W | 7360 W | 18.85 kW |
Applications
Where amps-to-watts conversion helps
Use it for planning, review, maintenance, and electrical education.
Battery and DC supply load checks
Residential appliance estimates
Heating-circuit load planning
Motor and pump power review
Solar inverter output planning
Generator load comparisons
UPS and transformer load checks
Panel schedule preparation
Workshop equipment review
Electrical training and formula practice
Good practice
Advantages, limitations, and common mistakes
A useful result depends on suitable inputs and engineering context.
Advantages
- Supports the three common circuit relationships.
- Makes current, voltage, and power-factor assumptions visible.
- Provides instant results and a copy action.
- Shows a live power-flow diagram.
- Keeps formula, examples, and a table together.
Limitations
- Three-phase results assume a balanced load.
- The calculation does not estimate starting or inrush current.
- AC accuracy depends on the correct power factor.
- It does not replace conductor, breaker, or protection design.
- Final work must follow local code and equipment data.
Common mistakes
- Using a DC formula for an AC load.
- Leaving power factor at 1 for an inductive load.
- Confusing line and phase voltage in three-phase work.
- Mixing amps with milliamps or kilowatts with watts.
- Treating calculated running power as a protection setting.
Safety
Electrical safety reminders
A watt calculation supports planning; it does not make live work safe.
Isolate and verify before working on conductors.
Use nameplate data for final calculations.
Allow for derating and continuous-load requirements.
Check starting current for motors and compressors.
Use correctly rated meters and PPE.
Treat high-current battery circuits as serious fault-energy hazards.
Conversion library
Explore all 44 electrical calculators
Continue from the Amps to Watts Calculator to a dedicated conversion tool for watts, amps, volts, kW, kVA, energy, batteries, or circuit calculations. Each linked page includes its own formula, examples, and guidance.
FAQ
Amps to watts questions
Short answers for common conversion questions.
How do I convert amps to watts?
Multiply amps by volts for DC. For AC, multiply by voltage and power factor; balanced three-phase also uses the square root of three.
What is the DC amps to watts formula?
Watts equal amps multiplied by volts.
Why does power factor matter?
It converts apparent AC power into real power, so it changes the watt result.
Can I calculate three-phase watts?
Yes. Use line voltage and the balanced three-phase formula shown on this page.
Are watts and volt-amperes the same?
They are the same only at unity power factor; otherwise real power in watts is lower than apparent power in VA.
Can this select a circuit breaker?
No. Use it as a load estimate, then apply code, duty, starting current, and installation requirements.
What voltage should I enter?
Enter the actual operating voltage from the equipment nameplate or measured supply.
Can I use it for solar batteries?
Yes for a DC estimate, but include inverter efficiency and cable losses in the system design.
What happens if PF is lower?
The same current and voltage produce fewer real watts.
Is this suitable for engineering design?
It is a useful first-pass calculation; final designs need qualified review and applicable standards.
Related resources
Continue learning
Move between complete calculators and electrical learning resources.
Amps to kW Calculator
Current to real power
Amps to kVA Calculator
Current to apparent power
Amps to VA Calculator
Current to volt-amperes
Electrical blog
Read practical guides about electrical formulas and planning.
Related formula
Use the inverse Watt to Amp formula when power is known and current is the unknown.