Inflation Calculator

How to use the inflation calculator

1. Choose a mode: Future cost (what something will cost later), Purchasing power (what your money will be worth later), or Cumulative inflation (the total price rise over the period).
2. Enter the amount in your currency — a price, a salary or a savings balance.
3. Enter the annual inflation rate published for your country, and the number of years.
4. Read the headline figure, then check the year-by-year table and download it as CSV if you need it.

All three modes share the same numbers, so you can switch between them without retyping anything.

How it works

Inflation compounds exactly like interest. Everything on this page comes from one factor:

factor = (1 + i)^t

where i is the annual inflation rate as a decimal and t is the number of years.

The two directions are mirror images: prices rising 34.39% is the same event as money losing 25.59% of its value. The percentages differ because they use different denominators — one compares to today’s price, the other to today’s money.

No historical CPI data is built in, and that is deliberate. Baked-in index tables are out of date the day after the next release, and they only cover a few countries. Instead you supply the rate, which makes the tool work for any currency, any country and any forward-looking assumption. For long-range planning, many people use their central bank’s target — commonly around 2% — while for the recent past the official published figure is the right input.

Worked examples

A weekly shop. Groceries that cost $100 today, at 3% inflation, cost $134.39 in 10 years and $180.61 in 20 years.

Cash sitting in a drawer. $100 held for 10 years at 3% inflation buys only $74.41 of today’s goods. Over 20 years it falls to $55.37 — nearly half the value gone.

A salary that stands still. A $50,000 salary needs to be $81,930.82 after 20 years of 2.5% inflation just to maintain the same lifestyle. If the salary never changes, its real value drops to $30,513.55.

A long retirement. $1,000 a month of spending today becomes $7,612.26 a month after 30 years at 7% inflation. The same $1,000 would buy only $131.37 of today’s goods. High inflation rates compound brutally over long horizons.

Reading the year-by-year table

The table lists every year of the period with three columns: what today’s basket costs by then, what today’s money is worth by then in today’s terms, and the cumulative inflation so far. Watching the two money columns drift apart makes the compounding obvious — the gap widens slowly at first and then accelerates, which is why long horizons matter far more than the headline rate suggests. Download the CSV if you want to chart it next to your own salary history or savings balance.

Tips and common mistakes

• Nominal is not real. A 6% return during 3% inflation is roughly 2.91% of real growth, not 3%. Divide the growth factors rather than subtracting the rates when precision matters.
• A 34% price rise is not a 34% loss of value. Rising prices and falling money value are the same thing measured from opposite ends; use the mode that matches the question you are answering.
• Averages hide volatility. A constant rate is a planning convenience. Real inflation swings year to year, and the categories you personally buy — rent, energy, tuition — can run far above the headline index.
• Rule of 70. Divide 70 by the inflation rate for a quick doubling time for prices: at 3%, prices roughly double in 23 years.
• Wage growth is the benchmark that matters. Compare your raise with inflation, not with zero. Anything below the inflation rate reduces your real income.

Results are estimates based on a constant rate you provide, and nothing here is financial advice.

Glossary

• CPI – consumer price index, the basket-based measure most countries use to report inflation.
• Nominal value – an amount as printed, before adjusting for inflation.
• Real value – an amount expressed in the purchasing power of a chosen base year.
• Deflation – a negative inflation rate, where prices fall and money gains value. Enter a negative rate to model it.
• Cumulative inflation – the total price increase across the whole period, not the yearly rate.

Last reviewed: September 21, 2026