Dollar bills can be tracked using an online application, such as Where's George. So that the bill's movements across the country can be tracked, users have to enter the denomination of the bill, serial number, bill series and the user's ZIP code.
The dollar bills are tracked by user inputs. When the dollar arrives with another user, that person goes to the website and enters the bill's information. Without other users entering the information, there is no way to track a particular dollar bill. To encourage people who handle the bill to go to the website, a stamp can be placed on the bill with the tracking website address to let others know that the bill's movements are being tracked.