How Fast Is Government Debt Growing?
Reading a live debt clock: rates per second, per day and per person, and what a model leaves out.
About 20 minutes · high school
The idea
A debt clock is a model. It starts from an official figure, such as the IMF’s estimate of a government’s debt at the end of 2025 or the US Treasury’s latest daily total, and adds a steady amount every second, based on how fast that debt is expected to grow. The real debt does not move smoothly: it jumps when bonds are sold and falls when they are repaid. The counter shows the trend.
Right now the world’s governments together add about $293,799 a second to their debt, and the United States about $79,753. Watch the US counter for a minute:
Worksheet
- At $293,799 a second, how much does world government debt grow in one minute? In one day?
- At that rate, about how many days does it take the world to add $1 trillion?
- US debt grows about $79,753 a second, and about 342.8 million people live in the United States. How much is that per person per year?
- Japan’s counter falls in US dollars even though its government keeps borrowing in yen. What could explain that?
- Name one thing a counter that ticks every second leaves out about real government debt.
Answer key
- About $17.6 million a minute and $25.4 billion a day.
- About 39 days: $1 trillion ÷ ($293,799 × 86,400 seconds).
- About $7,336 per person per year: $79,753 × 31,536,000 seconds ÷ 342.8 million.
- The exchange rate. When the yen loses value against the dollar, the same yen debt is worth fewer dollars, so the dollar figure can fall while the yen figure rises.
- Any one of: the real debt moves in steps, not smoothly; the rate is a projection that can be wrong; it does not show who the debt is owed to, what interest it carries, or what the money paid for.
To discuss
- Is a large number per second worrying on its own? Compare it with the size of the economy using the debt-to-GDP lesson.
- How could you check whether a debt clock is accurate? (This site checks its US counter against every Treasury close on its accuracy page.)
Words to know
- Rate
- How much something changes per unit of time, such as dollars per second.
- Model
- A simplified way of estimating something that cannot be measured continuously.
- Exchange rate
- The price of one currency in another.
- Record
- An official figure published by the government, such as the Treasury’s daily total.
Figures as of November 9, 2026, from the IMF World Economic Outlook (October 2026) and the US Treasury, as used across this site. These lessons are free to use, copy and adapt under CC BY 4.0; please credit Global Debt Clock. No sign-up, and no ads on these pages. Suggestions: [email protected].