While 230 V/50 Hz is used in Western Europe, 110-120 V and 60 Hz is common in the USA. The shape of the socket also differs: in America, two flat pins are used, which may be supplemented by a grounded cylindrical pin. Therefore, you cannot charge your electronics without a travel adapter.
USA Power Plugs and Sockets: Type and Line Voltage
Types A and B outlets are used in the United States. A type A outlet has two flat pins and is used for smaller electronics like cell phones. A type B plug also has a round ground pin, often seen on laptops. Both types of sockets are compatible with each other.
Today, virtually all phone, laptop, or tablet chargers are designed to accommodate both European and American voltage. You can check the functionality by looking at the label on the charger, which shows the permitted voltage values. Look for INPUT: 100V-240V 50/60Hz.
Travel Adapter for the United States
The classic set of travel adapters is fully sufficient. I recommend choosing adapters that allow you to connect a plug with a center ground pin. Cheaper adapters usually lack this feature, so you might not be able to charge your laptop, for example.
You can purchase a USA-style adapter at a regular electrical store. I recommend buying a set right away for use when traveling anywhere in the world.
My Travel Tips and Experiences
1️⃣ Bring an Extension Cord with Your Travel Adapter
One adapter for USA outlets is not enough for one person, let alone for multiple people. A better solution than a splitter or multiple adapters is a simple extension cord. It allows you to charge several devices simultaneously and solves the problem of limited outlet availability.
2️⃣ Power Bank as a Universal Power Source
I always take a power bank on all my trips. With it, I can charge my phone, headphones, watch, and in extreme emergencies, even my laptop. I use a power bank with a capacity of 20,000 mAh.
A very practical feature is the Pass-Through Charging function, which allows you to charge your device from a charged power bank. In the evening, you plug in a depleted power bank, connect a few low-battery devices, and wake up in the morning with everything fully charged.