PlugVoltage

Travel power guide

Where Is My Device's Voltage Label?

Direct answer

Where Is My Device's Voltage Label?

Look on the underside of the device, on the power plug itself, or on the charger/power brick — find the line that starts with "INPUT".

Updated 2026-09-04

V = volts (the most important number for safety). Hz = frequency. A and W = current and power. The ~ symbol means AC (normal household power).

"INPUT 100–240V~ 50/60Hz" means dual voltage; a single value like "120V" means single voltage.

If you can't find or read the label, don't plug in until you've confirmed it.

Sources and limits

What the evidence covers

A source supports only the facts, socket types or models listed below. A model example does not verify every device in its category. Confirm your own label and outlet.

  1. Apple: MacBook Pro USB-C power adapter specifications · checked: 2026-08-21

    Apple lists 100–240V AC, 50–60Hz for the named 70W, 96W and 140W USB-C power adapters. Power adapter specifications. A checked manufacturer family example; not proof for every USB, GaN or laptop charger.

  2. Conair: 1875 W Model 303 hair dryer instructions · checked: 2026-08-21

    Conair Model 303 specifies 110–125V AC, 60Hz and prohibits use with a voltage converter. PDF page 1, important safety and operating instructions. This label excludes Japan’s 100V. It does not describe every hair dryer.

  3. ResMed: AirSense 11 user guide · checked: 2026-08-21

    The AirSense 11 65W supply specifies 100–240V, 50–60Hz; typical and peak consumption differ. Technical specifications, printed page 22 (PDF page 25). Only the named supply and machine are covered. Confirm your own supply, accessories and manufacturer instructions.

Where to look

Common voltage-label locations

The label may be on the device, the plug, or a separate power brick.

Laptop charger Look on the rectangular brick, often near the cable strain relief or safety marks.
Hair tool Check the handle or hinge area. If the print is missing, do not guess abroad.
USB charger Read the wall brick itself; the phone, cable, or USB-C output text is not enough.
Illustrative examples

Label examples to recognize

Use these text patterns as visual cues before you trust a charger, hair tool, or adapter abroad.

Travel-safe AC input INPUT 100-240V~ 50/60Hz This is the wall-side range that usually works worldwide; you may still need a plug adapter.
Single-voltage warning INPUT 120V~ 60Hz This is not universal. Do not rely on a plug adapter in 220-240V countries.
Output is not input OUTPUT 20V ⎓ 3.25A USB-C output tells you what the charger sends to the device; it does not prove wall-voltage safety.

Step by step

  1. Look on the underside of the device, on the power plug, or on the charger/power brick.
  2. Find the line that starts with "INPUT".
  3. Read the voltage: "100–240V" means dual voltage; a single value like "120V" means single voltage.
Exact trip check

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

Open the checker

Related guides

What Does "100–240V" Mean? (Dual Voltage Explained) An input rating of 100-240V covers nominal voltages within that range. Confirm the frequency, plug, grounding … Adapter vs Converter: What's the Difference? A plug adapter changes the shape of your plug so it fits a foreign socket; a voltage converter changes the vol… Are All USB Chargers Dual Voltage? Almost all modern USB and USB-C chargers are dual voltage (100–240V) and work worldwide with just a plug adapt…

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.