Inflation Calculator

Inflation silently erodes the purchasing power of money — a dollar today buys less than a dollar did ten years ago and more than it will in ten years. Understanding this erosion is essential for sound financial planning. This calculator works in both directions: enter an amount and look forward to see what it would need to be worth in the future to maintain purchasing power, or look backward to find what a current sum was historically equivalent to. Use cases include comparing salaries across different decades to assess whether real wages have improved, calculating the true cost of long-term fixed-rate debt where inflation works in the borrower's favor, planning retirement savings targets, and understanding why savings accounts with sub-inflation yields actually lose real value year over year. Enter any amount, select a direction, choose the years, and set an inflation rate to get instant results.

Inflation adjustment uses compound growth: Future Value = Amount × (1 + Rate)^Years. To reverse it (find a past equivalent): Past Value = Amount ÷ (1 + Rate)^Years. The cumulative inflation percentage is (Future Value − Original) ÷ Original × 100. The "years until prices double" is derived from the Rule of 70: Years ≈ ln(2) ÷ ln(1 + Rate), which gives a precise answer (the Rule of 70 approximates this as 70 ÷ Rate%). All calculations assume a constant annual inflation rate throughout the period.