Guide · 5 min read
Converter or adapter? Read the label.
A plug adapter changes the shape of the prongs and passes the voltage straight through. A converter changes the voltage itself. The answer for almost every traveler is the adapter — and the label on your charger proves it in five seconds.
The five-second test
Turn the brick over and find the INPUT line. If it reads INPUT: 100–240V~ 50/60Hz, the device is dual-voltage: it already handles anything the world's mains can throw at it, and you need nothing but a plug adapter. If it reads a single value — INPUT: 120V 60Hz — it is single-voltage and will be damaged or destroyed on a 230V supply.
Every USB-C charger sold in the US is 100–240V. So are Apple and Samsung bricks, laptop power supplies, camera chargers, e-reader chargers and virtually every switching supply made this century. The switching topology that makes them small is also what makes them voltage-agnostic. This is why the "do I need a converter for my phone charger" question has the same answer everywhere: no.
| What you are packing | What it needs | Why |
|---|---|---|
| Phone, tablet, laptop chargers | Plug adapter only | 100–240V switching supplies |
| Camera, drone, power-bank chargers | Plug adapter only | Same |
| Electric shaver, toothbrush base | Usually adapter only | Nearly all are dual-voltage; check the label |
| Hair dryer, straightener, travel iron | Converter, or a dual-voltage model | Resistive heating element sized for one voltage |
| Travel kettle, coffee maker | Converter (high wattage) | Heating element; most travel converters cannot carry it |
| Corded appliances with motors | Converter, and check frequency | Motor speed and torque depend on volts and hertz |
| Medical devices (CPAP etc.) | Check the supply's own label | Many bricks are 100–240V; confirm before travelling |
What a converter actually is
Two very different products share the word. Step-down converters chop the waveform electronically. They are light and cheap, they are rated for resistive loads only, and they carry short duty limits — often a stated maximum run time measured in minutes. Feeding a laptop brick or anything with a motor through one is how equipment gets destroyed. Transformers are heavy iron-cored units that supply a clean stepped-down sine wave continuously, and are the correct choice for sensitive electronics — but since your electronics are already dual-voltage, you should not be buying one.
Frequency matters less than people fear. 50Hz versus 60Hz is irrelevant to a switching power supply, which rectifies to DC immediately. It matters for synchronous motors and mains-timed clocks, which run slow on 50Hz, and for some older appliances. No converter fixes frequency; that requires a full inverter.
What to pack instead
For most trips the correct kit is one grounded universal plug adapter plus one multi-port USB-C charger, covering the whole family from a single socket. That removes the need for four adapters and the temptation to buy a converter you do not need. Our full breakdown of the two product categories side by side is in travel adapter vs converter, and the country-by-country plug and voltage details are on the travel hub.
Check your destination before you leave: the UK and Ireland use Type G at 230V (UK guide), continental Europe is Type C/E/F at 230V (Europe guide), Japan is Type A/B at 100V (Japan guide), and Australia and New Zealand are Type I at 230V (Australia guide). The complete plug reference is in plug types by country, and if you are flying, airline rules for chargers and power banks covers what can travel where.
FAQ
Do I need a voltage converter for my phone charger in Europe?
No. Every USB-C charger sold in the US is rated 100-240V, so a plug adapter that changes the prong shape is all that is required. Confirm by reading the INPUT line on the brick.
What happens if I plug a 120V-only device into 230V?
It draws roughly double the intended current and usually fails immediately, often with smoke. Heating elements and motors are the devices where this actually happens, because they are not dual-voltage.
Can I run a hair dryer on a travel converter?
Only if the converter's wattage rating exceeds the dryer's, and only for its stated duty limit. Most travel dryers pull 1000-1800W, which is above what a compact converter can carry. A dual-voltage dryer is the better answer.
Does 50Hz versus 60Hz matter for my laptop?
No. Switching power supplies rectify mains to DC immediately, so frequency is irrelevant. It matters only for synchronous motors and mains-timed clocks.