Calculators
What the big numbers mean for your own money
Interest rates, inflation and federal borrowing are abstract until they show up in a mortgage payment, a credit card bill or a savings balance. These calculators do that translation for your own figures.
What a rate change does to your mortgage
See the monthly and lifetime cost of a home loan if rates move half a point, one point or two.
What your money was worth
What an amount from any year since 1950 is worth today, and how much buying power it has lost.
Where your federal tax goes
Your tax, split the way the government actually spent it, with interest on the debt as its own line.
What the minimum payment really costs
Years and interest on a card balance, and how much sooner you are debt free with a little extra.
Credit card and loan payoff planner
Compare the avalanche and snowball methods: months to debt-free, total interest and payoff order.
What a mortgage actually costs
Payment, total interest and a year-by-year schedule, starting from the current average rate.
What a car really costs
Tax, fees and interest on top of the sticker price, and what a longer term does to the total.
What one point costs your household
A rate rise applied to the mortgage, the car loan and the card at once — and to the federal budget.
Did your raise beat inflation?
Two salaries from two years, put into the same prices, plus the pay you would need to stay level.
Is your savings account beating inflation?
Your balance in future dollars and in today’s dollars, against current inflation and Treasury bills.
What your saving plan is really worth
Compound interest towards a goal, in future dollars and in what those dollars will buy.
What lending to the government pays
The debt from the creditor’s side: what today’s Treasury yields earn, before and after inflation.
Your household’s share of the national debt
The debt, this fiscal year’s interest bill and the daily growth, divided out for your household.
Your share of the debt, wherever you live
The same household share of government debt in 190 economies, with the US in the ranking.
Your household’s debt, next to the government’s
Debt against a year of income, for you and for the federal budget, measured the same way.
What the trust fund shortfall means for one benefit
The Trustees’ own “do nothing” scenario, applied to a monthly Social Security benefit.
How these calculators work
Every result is calculated in your browser as you type. Nothing you enter is sent to a server, stored or used to set a cookie, so you can try real numbers — your actual balance, your actual rate — without handing them to anyone.
Where a calculator starts from a published figure, the figure and its date come from the same build as the rest of this site: the national debt from the US Treasury, inflation from the Bureau of Labor Statistics, Treasury bill yields from the Treasury yield curve, and average credit card balances from the New York Fed. Each page names its sources and its assumptions. Example values are labelled as examples.
The maths is deliberately standard — the textbook amortization formula for loans, month-by-month simulation for debt payoff, compound interest deflated by a constant inflation rate for savings — so you can check any result against a spreadsheet. The trade-off is simplicity: real loans carry fees, taxes and insurance, card rates change, and inflation does not stay put.
These tools are educational. They are not financial advice, and they do not replace a quote from a lender or a conversation with a qualified adviser.
Why a debt clock has calculators
The federal debt reaches households mainly through interest rates. Government borrowing competes for the same savings that fund mortgages and car loans, and the interest bill on the debt is now one of the largest items in the federal budget. The Federal Reserve sets the short end of the rate curve — the federal funds rate — and the market sets the rest. For the top-down view, start with the national debt per person.