PlugVoltage

Travel power guide

What Wattage Converter Do I Need?

Direct answer

What Wattage Converter Do I Need?

Choose a converter rated for at least 25% more watts than your device draws — for example, a 1500W device requires at least about 1875W.

Find the wattage (W) on your device label. If only volts and amps are shown, multiply them (V × A = W).

Add headroom so the converter runs cool: required watts ≈ device watts × 1.25.

High-wattage heating appliances (1500W+) push past what most travel converters handle safely. For those, a dual-voltage travel model is the better buy.

If the label lists amps instead of watts, multiply the input voltage by amps. For example, 120V × 2A = 240W; with 25% headroom, choose a converter rated at least 300W.

Do not use the wattage of a USB output port to size a mains voltage converter. The number that matters is the AC INPUT load of the device or its charger.

If the result is close to a converter rating, round up, not down. A 240W load with 25% headroom is 300W exactly; a 250W load becomes 313W, so a 300W converter is already undersized.

Worked examples

Converter sizing examples

Use the AC input label, then add 25% headroom before choosing a converter rating.

120V x 2A label 120V x 2A = 240W. With 25% headroom, choose at least a 300W converter.
1500W hair dryer 1500W x 1.25 = 1875W. This is beyond what most compact travel converters handle safely.
65W USB-C output 65W is usually DC output to a laptop. Do not use it to size a mains voltage converter.

Step by step

  1. Find the wattage (W) on the device label. If only volts and amps are shown, multiply them: V × A = W.
  2. Multiply that by 1.25 to add headroom so the converter runs cool.
  3. Pick a converter rated at or above that number. For 1500W+ heating appliances, choose a dual-voltage travel model instead.
Exact trip check

Check your own device, label, and destination before you pack.

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Guidance only — not professional electrical advice. Always confirm against your device's label before plugging in. Local wiring (especially in hotels and older buildings) can vary.