livefree+
Treasury
The size and cost of the national debt, from a public fiscal service.
Metrics
National debt
live freeTotal public debt outstanding (daily); add ?series=true for the full daily history.
Average interest rate on marketable debt
live freeAverage interest rate on total marketable government debt (monthly); add ?series=true for history.
Pull Treasury data
Each metric above lists its endpoint. Requires thefree plan or higher. Get a key and start pulling live, fully sourced responses.