Inflation Calculator
Updated · By the CalculatorDash editorial team · How we check our maths
Quick answer
At 3% inflation, something that costs $100 today will cost about $134 in 10 years, and $100 kept in cash will buy only about $74 worth of today's goods.
How this calculator works
Inflation is the general rise in prices over time. Even moderate inflation compounds: at 3% a year, prices roughly double in 23 years. This calculator shows both sides: how much a fixed basket of goods will cost later, and how much less a fixed sum of money will buy.
Use it to set savings targets in future money, to check whether a pay rise actually beat inflation, or to understand why cash savings earning less than inflation lose value in real terms.
Official inflation figures, such as the US CPI or the UK CPIH, measure an average basket of goods. Your own inflation rate can differ a lot depending on what you buy: rent, childcare, insurance and food have often risen faster than the headline rate in recent years, while some electronics get cheaper.
The formula
- Future cost
- amount × (1 + inflation)^years
- Purchasing power
- amount ÷ (1 + inflation)^years
- Doubling time
- ln(2) ÷ ln(1 + inflation)
Worked example
At 3% a year, $100 grows to $100 × 1.03^10 = $134.39 in ten years. Kept as cash, $100 will buy only $100 ÷ 1.03^10 = $74.41 of today's goods, a 25.6% loss of purchasing power. Prices double in about 23.4 years.
Tips
- 01Compare savings rates with inflation; anything below it is a real-terms loss.
- 02Plan long-term goals, like retirement, in today's money and inflate them.
- 03Ask for pay rises that at least match inflation to keep your real income steady.
Frequently asked questions
How do you calculate inflation over several years?
Multiply by (1 + rate) once for each year: future price = today's price × (1 + rate)^years.
What is purchasing power?
How much a sum of money can buy. When prices rise, the same money buys less.
What inflation rate should I use?
Many central banks target about 2%. For long-term planning people often use 2–3% in the US, UK and Europe and around 4–6% in India.
What is the rule of 72 for inflation?
Divide 72 by the inflation rate to estimate how many years it takes prices to double. At 3%, about 24 years.