Inflation Calculator
See how inflation erodes purchasing power over time using official U.S. Bureau of Labor Statistics CPI-U data from 1913 to present.
$100 in 2000 equals
$186.99 in 2025
Price Multiplier
1.8699x
Annual Inflation Rate
254.00%
Purchasing Power Change
$100 in 2000 has the same buying power as $186.99 in 2025. Prices increased by 87.0%.
Frequently Asked Questions
What is the Consumer Price Index (CPI)?
The CPI measures the average change in prices over time that consumers pay for a basket of goods and services (food, housing, transportation, healthcare, etc.). It is the most widely used measure of inflation, published monthly by the U.S. Bureau of Labor Statistics.
How accurate is this calculator?
This calculator uses official BLS CPI-U (Consumer Price Index for All Urban Consumers) annual average data from 1913 to present. Results are historically accurate for the periods shown. Note that CPI methodology has changed over time, and past inflation does not predict future inflation.
Why does $1 today not buy what it used to?
Inflation erodes purchasing power over time. If inflation averages 3% per year, $100 today will only buy about $74 worth of goods in 10 years. This is why keeping money in a low-interest savings account actually loses value in real terms.
How can I protect against inflation?
Investing in assets that historically outpace inflation — such as stocks, real estate, and Treasury Inflation-Protected Securities (TIPS) — helps preserve purchasing power. Historically, the S&P 500 has returned about 10% annually before inflation, or about 7% after inflation.
What was the highest inflation period in US history?
The highest sustained inflation in modern US history was the late 1970s and early 1980s, with CPI increases of 11.3% (1979), 13.5% (1980), and 10.3% (1981). Use this calculator to see just how dramatically prices changed during that period.