Watts to Volts & Volts to Watts Calculator
Use our dual-mode conversion calculator to easily switch between converting power in Watts (W) to potential difference in Volts (V) and voltage to power. Our tool offers instant, accurate calculations based on circuit current draw in Amperes (A) to assist in checking electrical load compatibilities and sizing power supplies.
Watts to Volts Calculator
How to Use the Watts to Volts Calculator
Follow these simple steps to convert active power in Watts (W) to potential difference in Volts (V) using our online converter:
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1Enter active power rating in Watts (W) in the power input field.
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2Enter target continuous current draw in Amperes (A).
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3Click the Calculate to Volts button to compute total voltage.
How to Calculate Watts to Volts Manually
To convert active power in Watts (W) to electrical potential difference in Volts (V), divide the power in Watts by the continuous electrical current flow in Amperes (A). This division formula represents the standard relation derived from Joule's law of heating and Ohm's law.
Real-Life Scenarios
Scenario 1: Laptop Power Adapter Assessment
A laptop power charger consumes 65 Watts of continuous power. Sizing specifications indicate it provides a continuous current flow of 3.25 Amps. Sizing the output potential difference of the adapter yields:
Volts = 65 Watts / 3.25 Amps = 20.0 Volts
Scenario 2: Sizing Voltage for domestic space heater
An electric room space heater consumes 1500 Watts of active power under a current draw of 12.5 Amps. Sizing the required supply voltage parameter:
Volts = 1500 Watts / 12.5 Amps = 120.0 Volts
Step-by-Step Calculation Guide
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1Identify Parameters: Settle active power in Watts (W) and current flow in Amps (A).
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2Select the Formula: Use the potential difference formula:
Volts = Watts / Amps. -
3Compute: Divide the wattage value by the current rating to obtain the electrical potential difference in Volts.
Watts to Volts Conversion Chart
The chart below highlights conversion calculations from Watts to Volts (assuming a baseline current of exactly 1 Amp):
| Active Power (Watts) | Current Flow (Amps) | Potential Difference (Volts) |
|---|---|---|
| 5 W | 1 A | 5 V |
| 10 W | 1 A | 10 V |
| 20 W | 1 A | 20 V |
| 65 W | 1 A | 65 V |
| 100 W | 1 A | 100 V |
| 120 W | 1 A | 120 V |
| 500 W | 1 A | 500 V |
| 1,000 W | 1 A | 1000 V |
| 1,200 W | 1 A | 1200 V |
| 1,500 W | 1 A | 1500 V |
10 watts to volts
A rating of 10 Watts yields these voltage requirements:
- Current flow of 1 Amp:
10 / 1 = 10.0 Volts. - Current flow of 2 Amps:
10 / 2 = 5.0 Volts.
1000 watts to volts
A rating of 1000 Watts yields these voltage requirements:
- Current flow of 5 Amps:
1000 / 5 = 200.0 Volts. - Current flow of 10 Amps:
1000 / 10 = 100.0 Volts.
20 watts to volts
A rating of 20 Watts yields these voltage requirements:
- Current flow of 1 Amp:
20 / 1 = 20.0 Volts. - Current flow of 2 Amps:
20 / 2 = 10.0 Volts.
100 watts to volts
A rating of 100 Watts yields these voltage requirements:
- Current flow of 5 Amps:
100 / 5 = 20.0 Volts. - Current flow of 0.83 Amps:
100 / 0.83 ≈ 120.0 Volts.
1500 watts to volts
A rating of 1500 Watts yields these voltage requirements:
- Current flow of 12.5 Amps:
1500 / 12.5 = 120.0 Volts. - Current flow of 6.52 Amps:
1500 / 6.52 ≈ 230.0 Volts.
65 watts to volts
A rating of 65 Watts yields these voltage requirements:
- Current flow of 3.25 Amps:
65 / 3.25 = 20.0 Volts(standard USB-C Power Delivery sizing). - Current flow of 5.42 Amps:
65 / 5.42 ≈ 12.0 Volts.
1200 watts to volts
A rating of 1200 Watts yields these voltage requirements:
- Current flow of 10 Amps:
1200 / 10 = 120.0 Volts. - Current flow of 5.22 Amps:
1200 / 5.22 ≈ 230.0 Volts.
5 watts to volts
A rating of 5 Watts yields these voltage requirements:
- Current flow of 1 Amp:
5 / 1 = 5.0 Volts(standard legacy charger output). - Current flow of 0.5 Amps:
5 / 0.5 = 10.0 Volts.
120 watts to volts
A rating of 120 Watts yields these voltage requirements:
- Current flow of 10 Amps:
120 / 10 = 12.0 Volts. - Current flow of 1 Amp:
120 / 1 = 120.0 Volts.
FAQs About Converting Watts to Volts
No. Watts measure real power (rate of energy usage), while Volts measure potential difference. They are linked by current: Watts = Volts × Amps.
To convert Watts to Volts, divide power in Watts by continuous current in Amperes: Volts = Watts / Amps.
No. 120 Volts is standard electrical outlet pressure in North America, whereas 120 Watts represents power usage (e.g. running a 120-watt light bulb).
A resistive load drawing 1 Amp of current on a 220V power line consumes exactly 1 × 220 = 220 Watts of power.
1 Volt is defined as the potential difference that will force 1 Ampere of current through a resistance of 1 Ohm. It is also equal to 1 Joule of energy per coulomb of charge.
1 Volt is a very small potential. For comparison, a single standard AA battery provides 1.5 Volts, and a typical USB port outputs 5 Volts.