Travel Adapter and Voltage Matcher for Trips

Plug adapter vs. voltage converter — common questions

What is the difference between a plug adapter and a voltage converter?

A plug adapter only changes the shape of the prongs so your charger physically fits a foreign socket — it does not change the voltage. A voltage converter (or transformer) actually steps the wall voltage up or down. If your device's label says "100–240V" it is dual-voltage and an adapter is all you need. If it says a single voltage (e.g. "120V" or "230V"), you need a converter when the destination voltage is different, because the adapter alone would deliver the wrong voltage and damage the device.

How do I know if my device is dual-voltage?

Read the small print on the device or its charger, usually near the plug. "INPUT: 100–240V, 50/60Hz" means dual-voltage — it works worldwide with just a plug adapter. A single value like "120V" or "220–240V" means single-voltage. Almost all phone chargers, laptop bricks, camera chargers and modern GaN chargers are dual-voltage; the usual single-voltage culprits are hair dryers, curling irons, travel kettles and clothes irons.

Do I need a voltage converter for a US hair dryer in Europe?

Usually yes — and often it is not worth it. A typical US hair dryer is single-voltage (120V) and high-wattage (1500–1875W). European mains is 230V, so without a converter it would overheat instantly. But converters rated above ~2000W are bulky and expensive, so for heating devices over 1500W it is generally cheaper and safer to buy a dual-voltage travel hair dryer or use the one in your accommodation. This tool returns "buy local" for exactly that case.

Will a plug adapter protect my device from the wrong voltage?

No. A plug adapter is a passive shape-changer with no electronics inside — it passes the destination's full wall voltage straight through. Plugging a 120V-only device into a 230V socket through an adapter will still destroy it. Only a voltage converter or a genuinely dual-voltage device is safe across the 110–127V vs. 220–240V divide.

Does the 50Hz vs 60Hz frequency difference matter?

For electronics with switching power supplies — phones, laptops, tablets, cameras — frequency makes no practical difference. It matters for devices with an AC motor or an analogue clock: a shaver, electric toothbrush or hair-dryer fan may run slightly slower or warmer on 50Hz when designed for 60Hz (or vice versa). Japan is the tricky case because it runs 50Hz in the east and 60Hz in the west, so the calculator warns conservatively on motorised devices there.

Is one universal travel adapter enough for a multi-country trip?

For plug shape, yes — a single universal adapter covers Type A through Type O sockets, so it handles the US, UK, EU, Japan and Australia on one trip. What a universal adapter cannot do is convert voltage. So the rule is: one universal adapter for the prongs, plus a converter only if you are carrying a single-voltage device into a region with a different wall voltage.

My device is rated 100–127V. Is it safe in Brazil?

It depends on the city. Brazil has no single national voltage: São Paulo and Rio are 127V (safe for a 100–127V device with just an adapter), but Brasília, Recife and Fortaleza run 220V, which would destroy a 127V-only device. Always check the outlet label or ask at your accommodation before plugging in — this is the one country where "it worked in Rio" does not guarantee it is safe elsewhere.

Related tools

Other BorderTrip Tools for the power and packing side of your trip:

• Voltage converter & step-up/step-down checker — work out whether a single-voltage appliance needs a step-up or step-down converter and what wattage to buy.
• Travel power bank airline compliance checker — check the Wh limit and carry-on rules so your power bank is not confiscated at security.
• Cabin bag fit & fee checker — see whether your carry-on meets each airline's size limit before you are charged a gate fee.

BorderTrip Tools — all travel-readiness tools