Where can you find the amount of the United States national debt?

The U.S. Department of the Treasury provides a frequently updated official total of the U.S. national debt at its web site at TreasuryDirect.gov. The site breaks down debt into debt held by the public and intragovernmental holdings and also includes historical data dating back to 1993.

TreasuryDirect's total is typically one or two days out of date, but sites such as NationalDebtClocks.org provide an unofficial total of the U.S. national debt that is updated in real time. National Debt Clocks provides real-time national debt totals for 49 different countries as of September 2015 and notes that interest on the U.S. national debt accrues at a rate of $16,692 per second.