How to Calculate Amps from Watts (It’s Easier Than You Think!)

Need to figure out how much electrical current something uses? When you’re sizing a breaker, choosing a power supply, or if you’re just curious — calculating amps from watts is quick and simple.

Let’s break it down step by step and give you a handy calculator too!

🙋 First, What Are Amps?

• Amps (A) = measure of electrical current
• Watts (W) = measure of power
• Volts (V) = measure of electrical pressure

They’re all connected by a simple formula you’ll see below.

🔌 The Formula to Calculate Amps

Here’s the standard formula:

Amps = Watts ÷ Volts

That’s it! Just divide the power (watts) by the voltage to get the current in amps.

✅ This formula works for resistive AC loads (like heaters, toasters) or DC circuits.

⚙️ Example

Let’s say you have a device that uses 1200 watts, and it runs on 120 volts:

Amps = 1200 ÷ 120 = 10 amps

So your device draws 10 amps of current.

🔋 Common Voltage Reference Chart

Country or System	Standard Voltage
USA / Canada	120 V
Europe / Asia	230 V
Car battery (DC)	12 V
USB port (DC)	5 V

🔁 Related Posts

• Watt vs Volt - What's the difference?