Inflation calculator

Inflation calculator: the basics

Explore how a constant assumed inflation rate could change prices and the buying power of money held at the same nominal amount.

How to use the inputs

• Current amount: Enter a present-day amount from zero to 1 billion.
• Assumed annual inflation: Choose an assumed annual inflation percentage from 0 to 50. This is not live data or a country forecast.
• Time period: Choose a whole number of years from 1 to 60.

Change an input to update the results. Add up to four scenarios to compare separate assumptions; reset affects only the selected scenario.

Understanding the results

• Estimated future cost is what today’s amount would cost after inflation. Total price increase is future cost minus today’s amount.
• Future purchasing power is the unchanged nominal amount expressed in today’s buying power. Purchasing-power loss is today’s amount minus that purchasing power.
• The chart shows estimated future cost at each year-end, not a forecast of actual inflation.

The formula, in words

Let A be the current amount, i the annual inflation percentage divided by 100, and Y the whole number of years. Price factor F = (1 + i) raised to Y.

Future cost = A × F. Future purchasing power = A / F. Price increase = A × F − A. Purchasing-power loss = A − A / F.

Assumptions and limits

• Inflation compounds once per year at a constant user-supplied rate. At 0%, future cost and purchasing power both equal the current amount and both changes are zero.
• The nominal money earns no investment return. No contributions, tax rules, fees, exchange-rate changes or country-specific price baskets are applied.
• Negative inflation (deflation) is outside the supported 0–50% range. Personal spending can experience a different inflation rate.

Currency results display whole units; other numbers show at most one decimal place. Calculations keep full precision unless whole units must be rounded up for break-even. Rounded figures may not add up exactly.

Results of a trillion or more use scientific notation with up to three decimal places; for example, 1E12 means one trillion. Very small gains may round to zero.

Examples below use USD and local number formatting. Country selection changes currency labels, formatting and terminology; it does not convert money or automatically apply local tax or lender rules.

Worked example

This fixed example uses the calculator’s default inputs; it does not change when you edit a scenario. Any example interest or return rate is an assumption, not a guaranteed outcome.

Current amount

USD 10,000

Assumed annual inflation

3%

Time period

10 years

An assumed 3% compounded for ten years gives a price factor of about 1.343916. Multiplying USD 10,000 gives USD 13,439; dividing instead gives USD 7,441 of today’s buying power.

Estimated future cost

USD 13,439

Future purchasing power

USD 7,441

Total price increase

USD 3,439

Purchasing-power loss

USD 2,559

Common questions