US Dollar · $ · Official currency of the United States
The US dollar ($) was first established by the Coinage Act of 1792, and the modern Federal Reserve Note began circulating after the Federal Reserve System was created in 1913. It's the world's most widely used reserve currency, and several countries — including Ecuador, El Salvador, and Timor-Leste — have officially adopted it as their own currency instead of issuing their own.
Seven denominations circulate: $1, $2, $5, $10, $20, $50, and $100 ($2 bills are printed in small quantities and rarely seen in daily use). All notes are the same size and feature portraits of past presidents and other historical figures; security features and colors have been progressively updated since the 2000s.
Because the dollar circulates well beyond the US itself, it's worth keeping a stock of small bills ($1, $5, $10) handy for tips and small purchases wherever you're traveling. Since every denomination is the same size, it's easy to mix up bills at a glance — double-check the number, especially when you're handed a mix of older and newer designs. Cards and mobile payments cover most everyday spending in big cities, but small cash still comes in handy for tipping at restaurants and cabs.
You can view the real banknote designs on the Federal Reserve Bank of San Francisco's official page.
See US Dollar banknotes at today's exchange rate →