Calculates the equivalent value of the U.S. dollar in any month from 1913 to 2026.
Calculations are based on the average Consumer Price Index (CPI) data for all urban consumers in the U.S.
in=?in
Forward Flat Rate Inflation Calculator
Calculates an inflation based on a certain average inflation rate after some years.
with inflation rate%afteryears=?
Backward Flat Rate Inflation Calculator
Calculates the equivalent purchasing power of an amount some years ago based on a certain average inflation rate.
with inflation rate%=?years ago
About This Inflation Calculator
This powerful inflation tool uses official U.S. Bureau of Labor Statistics CPI data dating back to 1913. It helps you understand how inflation erodes purchasing power over time, project future costs, or calculate historical equivalents. Whether you're a student, retiree, or financial planner, accurate inflation insights are critical for budgeting and investment decisions.
How to Use
1. CPI Inflation Calculator — Enter an amount, select the starting month/year and ending month/year, then click Calculate to see the inflation-adjusted value.
2. Forward Flat Rate — Enter an amount, inflation rate (%), and number of years to see what the amount will cost in the future.
3. Backward Flat Rate — Enter an amount, inflation rate, and years ago to find out how much purchasing power that amount had in the past.
4. Use Clear buttons — Reset any calculator to its default values with one click.
5. Year-by-Year Tables — Each result includes a detailed breakdown table showing annual changes.
How It Works & Formula
Inflation measures the rate at which the general level of prices for goods and services rises, eroding purchasing power. This calculator uses the Consumer Price Index (CPI), which tracks price changes for a basket of consumer items.
Adjusted Value = Amount × (CPItarget / CPIsource)
Where:
• CPIsource = Consumer Price Index for the original month/year.
• CPItarget = Consumer Price Index for the destination month/year.
• The ratio (CPI_target / CPI_source) represents the cumulative inflation factor.
• For forward projections: Future Value = Present Value × (1 + r)n
• For backward calculations: Past Value = Present Value ÷ (1 + r)n
Mathematical Expression
Aadj = A × (It / Is)
Where Aadj is inflation-adjusted amount, It is target CPI, Is is source CPI. A ratio greater than 1 indicates inflation (higher future cost), while less than 1 indicates deflation.
Real-Life Example
Scenario: You want to know how much $1,000 from January 2000 is worth in March 2026.
CPI January 2000: 172.2 | CPI March 2026 (est.): 322.0
Adjusted Value = $1,000 × (322.0 / 172.2) = $1,870.38
What cost $1,000 in January 2000 now costs approximately $1,870.38 in March 2026 — a cumulative inflation rate of about 87% over 26 years.
Tip: Use the Year-by-Year breakdown table to see the impact of inflation each year and identify periods of high inflation.
Historical U.S. CPI Data (1913–2026)
Average annual Consumer Price Index (CPI-U) values showing long-term inflation trends.
Year
CPI
Year
CPI
Year
CPI
Data source: U.S. Bureau of Labor Statistics · CPI-U, All Urban Consumers, All Items · Base period: 1982–84 = 100 *Values for 2025-2026 are estimates based on recent trends.
Frequently Asked Questions
What is the Consumer Price Index (CPI)? +
The Consumer Price Index (CPI-U) measures the average change over time in prices paid by urban consumers for a market basket of consumer goods and services. It's the most widely used measure of inflation in the United States, published monthly by the Bureau of Labor Statistics.
How accurate are the inflation calculations? +
Our calculator uses official BLS CPI data, which is the standard reference for U.S. inflation. For recent years, we include monthly CPI values. For earlier years, annual averages are used. Projections beyond the current year are estimates based on recent trends and should be considered educational, not financial guarantees.
What's the difference between nominal and real value? +
Nominal value is the face amount of money without adjusting for inflation. Real value accounts for inflation, reflecting purchasing power. For example, $100 in 1990 has a much higher real value (buying power) than $100 in 2026 because prices have risen over time.
Why does the calculator use 2026 projections? +
We provide CPI estimates for 2025-2026 based on recent inflation trends and economic forecasts. These projections help with forward planning but actual future CPI may vary due to changing economic conditions.
How is the average annual inflation rate calculated? +
The average annual rate is the compound annual growth rate (CAGR) of CPI over the period: (CPI_end / CPI_start)^(1/years) - 1. This gives a consistent rate that would produce the same cumulative inflation over the given timeframe.
Can I use this for non-U.S. currencies? +
This calculator specifically uses U.S. CPI data. For other countries, different inflation indices would be required. However, the methodology (adjusting by price index ratios) remains the same globally.