Methodology

How the counter works

The live counter on USDebtClock.co is not a guess or an estimate pulled from thin air. It is built on official U.S. Treasury data and a transparent interpolation method described in full below.

Data source

The baseline debt figure comes from the U.S. Treasury Fiscal Data API - specifically the Debt to the Penny dataset, which records the total public debt outstanding for every business day since 1993.

API endpoint used:

https://api.fiscaldata.treasury.gov/services/api/v1/
accounting/od/debt_to_penny
?fields=record_date,tot_pub_debt_out_amt
&sort=-record_date&page[size]=2

This dataset is published by the Bureau of the Fiscal Service, a bureau of the U.S. Department of the Treasury. It is the same source used by the Congressional Budget Office, the Federal Reserve, and major financial institutions.

Update frequency

The Treasury publishes new debt figures on every business day, typically by 3:00 PM ET. Our system fetches the latest figure automatically each day at 18:00 UTC via a Cloudflare Worker cron job, ensuring the baseline is never more than 24 hours stale.

Real-time interpolation

The Treasury only publishes one figure per day - a daily total. To produce a counter that updates every second, we interpolate between daily readings using the trailing 30-day average daily growth rate.

daily_growth = debt_today - debt_yesterday
per_second_rate = trailing_30d_avg_daily_growth ÷ 86,400

current_debt = baseline + (seconds_elapsed × per_second_rate)

The per-second rate is recalculated each time a new Treasury figure is fetched. As of June 2026, the rate is approximately $105,324 per second, based on a 30-day average daily increase of ~$9.1 billion.

Step by step

1Cloudflare Worker fetches the two most recent records from the Treasury API at 18:00 UTC daily.
2The difference between the two records gives the daily growth. A sanity check rejects negative values or values above $500,000/sec (data errors).
3The latest debt total and per-second rate are stored in Cloudflare KV with a 48-hour TTL as fallback.
4When a visitor loads the page, JavaScript fetches the stored values and sets the baseline timestamp to the Treasury record date at 17:00 UTC.
5A requestAnimationFrame loop runs continuously, computing the current debt as baseline + elapsed seconds × per-second rate, and updates the display on every frame.

Per-citizen and per-taxpayer figures

Debt per citizen is calculated by dividing total debt by the U.S. resident population estimate of 329,484,123 (U.S. Census Bureau, 2023 estimate). Debt per taxpayer uses an estimate of 140,000,000 individual tax filers based on IRS Statistics of Income data.

Debt-to-GDP ratio

GDP is based on the most recent annualized nominal GDP estimate from the U.S. Bureau of Economic Analysis. As of Q1 2026, this figure is approximately $29.3 trillion. The ratio is recalculated in real time as the debt counter grows.

Historical data

The historical chart uses annual snapshots from the Treasury Fiscal Data API going back to 1980, supplemented by Congressional Budget Office historical tables for pre-1993 figures.

Disclaimer: The counter is an interpolated estimate based on official data and mathematical extrapolation. It does not represent the exact debt at any given millisecond - no public source provides that figure. The actual debt may differ slightly from the displayed value depending on intraday Treasury activity. This site is not affiliated with the U.S. government.

Questions or corrections

If you spot an error in our methodology or data, contact contact@nicename.me.