What this calculator does
The Inflation Calculator shows what a price or amount of money does over time when inflation runs at a steady rate. Enter an amount, an average annual inflation rate and a number of years. The calculator answers both questions at once:
- Future cost: what something that costs A today will cost after n years of inflation.
- Purchasing power: what money worth A today will actually buy after n years.
Use it to sanity-check long-term plans — a salary you can live on, a savings goal, a rent budget, or the real size of a fixed pension.
How to use the Inflation Calculator
- Enter the amount. A price you want to project (e.g. 100 of weekly groceries) or money you hold.
- Enter the average annual inflation rate. Use a long-run average or your country's CPI figure, as a percentage (e.g. 3).
- Enter the number of years. For example 10.
- Click "Calculate". The future cost, the future purchasing power and the total price rise appear below the button.
- Test other scenarios. Change the rate or horizon and recalculate to compare.
Formula
Inflation compounds, so the calculator uses exponential growth:
- A: today's price or amount
- r: annual inflation rate as a decimal (5% → 0.05)
- n: number of years
The total percentage rise is (1 + r)^n − 1, which is always larger than r × n when r is positive — the compounding effect.
Example
Say a basket of shopping costs 100 today and inflation averages 3% for 10 years.
- (1 + r)^n = 1.03^10 ≈ 1.34392
- Future cost = 100 × 1.34392 ≈ 134.39
- Total price rise ≈ 34.4% — not the naive 30%
- Purchasing power = 100 ÷ 1.34392 ≈ 74.41, so in ten years 100 buys what only about 74.41 buys today
Reading the second result backwards: to find what a price of 100 was worth 10 years ago at 3% average inflation, the answer is 74.41.
Frequently asked questions
What is inflation?
Inflation is the rate at which the general level of prices rises over time. At 5% inflation, a basket of goods costing 100 today costs about 105 a year from now.
How is future cost calculated?
Using compound growth: future cost = amount × (1 + rate)^years. Each year's increase applies to the already-inflated price, which is why the effect grows faster than a simple percentage.
What does purchasing power mean?
Purchasing power is how much stuff your money can buy. If prices rise 5% a year, 100 in cash buys about as much in ten years as 61 does today.
Which inflation rate should I use?
Use the average annual rate that fits your plan: a long-run historical average (around 2–4% in many countries), your national CPI figure, or a personal rate based on the things you actually buy.
Can I calculate a past price with this tool?
Yes. To find what today's price was n years ago, enter the average rate for those years and read the purchasing-power result — that is the equivalent past value.
Why is compounding so important?
Inflation builds on itself. At 5% for 10 years the total rise is not 50% but about 63%, because each year's increase is applied to a higher base. The calculator compounds automatically.
Related calculators
Other free calculators commonly used with this tool: Salary Calculator, Loan EMI Calculator, Mortgage Calculator, and Percentage Calculator.
Want a deeper walkthrough? Read our inflation guide.