Inflation is the silent tax on cash: prices creep up, so the same money buys less every year. This calculator shows both sides of that erosion — what today's amount will cost in the future, and what today's money will actually be worth in purchasing power.
Cómo funciona
Enter an amount, the expected annual inflation rate, and the number of years. The calculator compounds prices upward to show the future cost of today's basket, and discounts your money downward to show its future real value.
La fórmula
A is the amount, r the annual inflation rate as a decimal, and t the number of years. The two results are mirror images of the same compounding process.
Ejemplo resuelto
1,000 at 3% inflation over 10 years: what costs 1,000 today will cost about 1,344, and 1,000 kept as cash will buy only what 744 buys today — a quarter of its purchasing power gone in a decade.
Preguntas frecuentes
Why does even low inflation matter so much?
Because it compounds. At just 3%, prices double roughly every 24 years (the Rule of 72). Over a 30-year retirement, that halves the real value of a fixed income twice over.
How do I calculate my real investment return?
Approximate it by subtracting inflation from the nominal return: 7% return with 3% inflation is roughly a 4% real return. Precisely: (1.07 ÷ 1.03) − 1 ≈ 3.88%.
What inflation rate should I plug in?
Many central banks target around 2%; long-run historical averages in many economies sit between 2% and 4%, with much higher spikes possible. Test a range rather than one number.