Inflation Calculator
See how inflation erodes purchasing power and calculate the real value of money over time.
What is Inflation?
Inflation is the rate at which the general level of prices for goods and services rises, eroding purchasing power. When inflation occurs, each unit of currency buys fewer goods and services.
Purchasing Power = Original Amount ÷ (1 + inflation rate)^years
For example, at 3% annual inflation, prices double approximately every 24 years (the “Rule of 72”).
Historical Inflation Impact
Here’s how $100 from different decades would need to grow to have the same purchasing power today:
The Rule of 72
A quick way to estimate how long it takes for prices to double (or purchasing power to halve):
Protecting Against Inflation
- Invest in stocks: Historically, equities have outpaced inflation over the long term (~10% vs ~3%).
- Consider TIPS: Treasury Inflation-Protected Securities adjust with inflation.
- Real estate: Property values and rents typically rise with inflation.
- I Bonds: US savings bonds with inflation-adjusted interest rates.
- Commodities: Gold and other commodities often serve as inflation hedges.
Important Considerations
- Inflation varies by category: Healthcare, education, and housing often inflate faster than the average.
- Personal inflation rate: Your actual inflation depends on what you spend money on.
- Wage growth matters: If wages grow faster than inflation, you’re gaining purchasing power.
- Deflation risk: Rarely, prices can fall—this brings its own economic challenges.
- Future uncertainty: Past inflation rates don’t guarantee future rates.
Frequently Asked Questions
How does the inflation calculator adjust a historical amount to today?
Select a starting year, enter the original amount, and the calculator applies cumulative inflation at the rate you specify: Adjusted = Original × (1 + r)^n. For example, $1,000 in 2004 at 3% annual inflation would be equivalent to $1,000 × 1.03^20 ≈ $1,806 in purchasing power today. The calculator also shows the percentage of purchasing power lost.
What inflation rate should I use?
The US average CPI inflation rate has been approximately 3% over the past century, though it varies significantly by period — under 2% from 2010–2020 and over 8% in 2022. The calculator defaults to 3.0%. For conservative long-term financial planning, 3% is a common assumption; for near-term projections, check the current CPI rate at bls.gov.
Can I project future prices rather than look up historical equivalents?
Yes — the calculator has three modes: Past-to-Present (adjust a historical amount to today’s dollars), Present-to-Future (project a current amount to a future year), and Custom Period (from any year to any other year). The formula is the same in all modes; only the direction and reference points change.
Why does the calculator show the price multiplier separately?
The price multiplier (Adjusted Value / Original Value) directly shows how many times more expensive something has become. A multiplier of 1.8 means prices have risen 80%. It is often more intuitive than the cumulative percentage for understanding the real-world impact of inflation over time.
Does this calculator use actual CPI data?
No — it applies a uniform inflation rate you supply, not historical CPI data by year. Actual historical inflation varied from near-zero to over 14% annually. For exact historical CPI adjustments, the Bureau of Labor Statistics CPI Inflation Calculator at bls.gov uses the official month-by-month figures.