Is your savings account beating inflation?
Enter your balance, your account’s APY and how long you plan to save. See what the money grows to, what it will actually buy, and whether it is gaining or losing ground.
Your savings
Starts at 4% as an example, not a quoted rate.
Starts at the CPI 12-month change for August 2026: 3.4%.
At 4% APY and 3.4% inflation your money gains 0.58% in purchasing power per year — about $58 on $10,000 in the first year.
| Where the money sits | Rate | Balance | Today’s dollars | Real / year |
|---|---|---|---|---|
| Your savings account | 4% | $29,472 | $21,096 | +0.58% |
| 3-month Treasury billyield as of September 18, 2026 | 4.14% | $29,777 | $21,315 | +0.72% |
| Cash earning nothing | 0% | $22,000 | $15,748 | −3.29% |
Assumes the rates stay constant for the whole period, interest compounds monthly and deposits land at the end of each month. Before taxes. Treasury bill yields change at every auction and are not an APY.
Educational estimate, not financial advice. Everything is calculated in your browser — nothing you enter is sent anywhere or saved.
How this calculator works
The APY is converted to a monthly rate, (1 + APY)1/12 − 1, so interest compounds monthly and exactly matches the stated APY over a year. Monthly additions are made at the end of each month. The balance in today’s dollars divides the result by (1 + inflation)years. Everything is before tax, and the rates are held constant for the whole period.
The inflation field starts at the latest 12-month change in the Consumer Price Index (August 2026); the Treasury bill row uses the 3-month constant-maturity yield for September 18, 2026. Both come from this site’s last data build. Past inflation says little about the next ten years, so try a few rates.
Short-term yields follow the federal funds rate. The same yields set what the government pays to borrow — see interest on the national debt and the debt per person.
Common questions
Is my savings account beating inflation?
Only if its APY is above the inflation rate. Consumer prices rose 3.4% in the 12 months to August 2026, so an account paying less than that is losing purchasing power, even though the balance goes up.
What does “in today’s dollars” mean?
It is the future balance divided by how much prices will have risen by then, at the inflation rate you enter. It answers the question “what will this money buy, measured in prices I know today?”
How is the real return calculated?
As (1 + APY) ÷ (1 + inflation) − 1. For example, $10,000 at 0.5% APY with 3.4% inflation grows to $10,511 in 10 years but buys only what $7,527 buys today.
Why compare with a 3-month Treasury bill?
Treasury bills are short-term loans to the US government and a common benchmark for what cash can earn at close to no credit risk. Their yield moves with the Fed’s policy rate. Money market funds and high-yield savings accounts tend to pay rates in the same neighbourhood; ordinary savings accounts often pay far less.
Sources
- Inflation (CPI-U, 12-month change)US Bureau of Labor Statistics — Consumer Price IndexAugust 2026
- 3-month Treasury bill yieldUS Treasury — Daily Treasury Par Yield Curve RatesSeptember 18, 2026
All figures are fetched from the publishers above when this site is built; your browser does not contact them. This site is independent and is not affiliated with, sponsored or endorsed by the Federal Reserve System, any Federal Reserve Bank or any government agency. Nothing here is financial advice.