Inflation

1. Enter the **starting amount** — the present-day cost of an item, a salary, or any dollar figure you want to adjust for inflation.
2. Input the **annual inflation rate** as a percentage. Use a historical average (e.g., ~3% for the U.S. long-term average) or a custom rate. Leave blank to use the default.
3. Enter the **number of years** — how far into the future (or past) you want to project the value.
4. Choose whether you want to calculate **future cost** (how much more something will cost) or **purchasing power** (what today's money buys in the future).
5. Click **Calculate** to instantly see your result, including the inflated future cost and the real purchasing power loss over the period.

FV = PV × (1 + r)^n

Purchasing Power = PV ÷ (1 + r)^n

• FV — Future Value — the amount of money (in future dollars) that will have the same purchasing power as PV today, after n years of inflation at rate r.
• PV — Present Value — the current dollar amount you are starting with (e.g., the price of a good or service today, or a salary).
• r — Annual Inflation Rate — expressed as a decimal (e.g., 3% entered as 0.03). Typically based on the Consumer Price Index (CPI) or a user-chosen estimate.
• n — Number of Years — the time period over which inflation compounds (e.g., 10 years into the future or back into the past).
• Purchasing Power — The real value in today's dollars of a given amount received n years from now, showing how inflation reduces what money can actually buy.

FV = $30,000 × (1 + 0.03)^15
= $30,000 × (1.03)^15
= $30,000 × 1.55797
≈ $46,739

Result: Future Cost ≈ $46,739 Purchasing Power of $30,000 in 15 years ≈ $30,000 ÷ 1.55797 ≈ $19,257

At a steady 3% annual inflation rate, a car that costs $30,000 today will cost approximately $46,739 in 15 years — an increase of nearly $16,739. Conversely, $30,000 in 15 years will only buy what $19,257 buys today, meaning inflation will have eroded more than one-third of its purchasing power. This illustrates why saving and investing to outpace inflation is critical for long-term financial health.

Note: These are estimates based on a constant inflation rate. Actual inflation varies year to year. Results may differ from official CPI adjustments or lender/bank calculations.

What Is Inflation?

Inflation is the general increase in prices across an economy over time, meaning each unit of currency buys fewer goods and services as time passes. It is most commonly measured using the Consumer Price Index (CPI), published monthly by the U.S. Bureau of Labor Statistics (BLS), which tracks the average change in prices paid by urban consumers for a basket of goods and services.

Why Does Inflation Matter?

• Savings erosion: Money sitting in a low-interest account loses real value if the interest rate is below inflation.
• Salary negotiation: A raise below the inflation rate is effectively a pay cut in real terms.
• Retirement planning: Future retirees must account for decades of inflation when estimating how much they need to save.
• Fixed-income investments: Bonds and annuities can lose real value when inflation rises unexpectedly.

Historical U.S. Inflation Rates

The long-term average U.S. CPI inflation rate from 1913 to the present is approximately 3.1% per year. However, rates have varied widely:

• 1970s: Peak inflation above 13% (1979)
• 1980s–2010s: Gradual decline, averaging 2–4%
• 2021–2022: Inflation surged to 7–9% (post-pandemic supply shocks)
• Federal Reserve target: 2% per year is the official target for price stability

Rule of 70: Quick Mental Math

A useful shortcut: divide 70 by the annual inflation rate to estimate how many years it takes for prices to double.

• At 3.5% inflation → prices double in ~20 years (70 ÷ 3.5 = 20)
• At 7% inflation → prices double in ~10 years (70 ÷ 7 = 10)

Real vs. Nominal Values

• Nominal value: The face value in current dollars (not adjusted for inflation).
• Real value: Adjusted for inflation, reflecting actual purchasing power.

When comparing financial figures across different time periods, always convert to real (inflation-adjusted) values for a fair comparison.

• **Using a nominal interest rate instead of an inflation rate** — the inflation rate and an investment's return rate are different things. Enter the CPI-based inflation rate, not your portfolio return.
• **Forgetting to convert the rate to a decimal** — entering 3 instead of 0.03 will produce wildly incorrect results. Most calculators handle this automatically, but be aware of the input format.
• **Assuming inflation is constant** — real inflation fluctuates annually. A single average rate is a useful approximation, but actual future costs may differ significantly.
• **Confusing future cost with purchasing power** — these are inverse calculations. Future cost tells you what something will cost; purchasing power tells you what today's money will buy later. Make sure you are solving for the right direction.
• **Ignoring compounding** — inflation compounds exponentially, not linearly. A common error is multiplying: $30,000 × 0.03 × 15 = $13,500 (linear), which underestimates the true $16,739 increase from compounding.

• CPI Inflation Calculator — U.S. Bureau of Labor Statistics (BLS)
• Consumer Price Index (CPI) — Overview — U.S. Bureau of Labor Statistics (BLS)
• Monetary Policy: The Federal Reserve's Inflation Target — Board of Governors of the Federal Reserve System
• Historical Inflation Rates: 1914–2024 — U.S. Inflation Calculator (citing BLS CPI data)
• Treasury Inflation-Protected Securities (TIPS) — U.S. Department of the Treasury

Only sources that have been reviewed are shown. Unverified citations are never published.