Voltage Converter Wattage Calculator
Use the watts on your device label, or calculate watts from volts × amps, then add safe headroom before choosing a converter.
Use the W number from the label when available.
If the label says 120V 2A, that is 240W.
- Device load
- 150W
- Headroom
- × 1.25
- Minimum converter
- 200W+
Choose a converter rated at least 200W. This does not make the plug fit; you may still need a plug adapter.
How much headroom do I need?
For small electronics, choose a converter rated at least 25% above the device wattage. For motors or heat-producing gear, use more headroom — and avoid travel converters entirely for high-watt appliances.
When not to use a converter
Hair dryers, kettles, curling irons, and flat irons can draw 1000–3000W. A travel converter that claims to handle that load is often bulky, hot, or unsafe in real use. A dual-voltage travel model or a local appliance is the safer answer.
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