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Inflation Calculator

What Is Inflation?

Inflation is the rate at which the general level of prices for goods and services rises over time, eroding purchasing power. When inflation occurs, each unit of currency buys fewer goods and services than before. The U.S. Federal Reserve targets an inflation rate of about 2% per year as healthy for economic growth. Moderate inflation encourages spending and investment, while very high inflation (hyperinflation) or deflation can be economically destructive.

How the Consumer Price Index Works

The Consumer Price Index (CPI) is the most widely used measure of inflation in the United States. Published monthly by the Bureau of Labor Statistics (BLS), it tracks price changes for a 'basket' of approximately 80,000 goods and services across 8 major categories: food, housing, apparel, transportation, medical care, recreation, education, and other goods. The CPI-U (All Urban Consumers) covers about 93% of the U.S. population. The base period is 1982-84 = 100, meaning if today's CPI is 320, prices have risen 220% since the early 1980s.

Understanding Purchasing Power

Purchasing power measures how much you can buy with a given amount of money. When inflation rises, purchasing power falls — meaning you need more money to buy the same goods. For example, $1 in 1913 had the purchasing power of roughly $32 today. This is why simply saving cash loses value over time. To preserve purchasing power, your money needs to grow at least as fast as inflation. This is the fundamental reason why investing matters: a savings account earning 0.5% while inflation runs at 3% means you're losing 2.5% of purchasing power every year, even though your nominal balance grows.

Notable Inflation Periods in US History

The US has experienced several significant inflation events. The post-WWI spike (1917-1920) saw inflation reach 18%. The Great Depression brought severe deflation (-10.3% in 1932). The 1970s 'Great Inflation' peaked at 13.5% in 1980, driven by oil crises and loose monetary policy — Federal Reserve Chair Paul Volcker famously raised interest rates to 20% to tame it. The 2008 financial crisis brought near-deflation. Most recently, post-COVID stimulus combined with supply chain disruptions pushed inflation to 8% in 2022, the highest in 40 years. The Federal Reserve responded with aggressive rate hikes from near-zero to over 5% between 2022-2023.

Frequently Asked Questions

What is the current US inflation rate?

As of late 2025, the trailing 12-month inflation rate in the US is approximately 2.7%, measured by the Consumer Price Index (CPI). The Federal Reserve's target inflation rate is 2% per year. Inflation peaked at 9.1% in June 2022 before declining through 2023-2025 due to Federal Reserve rate hikes.

How is inflation calculated?

Inflation is calculated using the Consumer Price Index (CPI). The Bureau of Labor Statistics tracks prices of about 80,000 goods and services monthly. The inflation rate between two periods equals: ((CPI_new - CPI_old) / CPI_old) × 100. For example, if CPI went from 260 to 270, inflation is (10/260) × 100 = 3.85%.

What's the difference between CPI and PCE?

CPI (Consumer Price Index) and PCE (Personal Consumption Expenditures) both measure inflation but differ in scope and weighting. CPI covers only out-of-pocket consumer spending, while PCE includes spending on behalf of consumers (like employer health insurance). The Federal Reserve prefers PCE for policy decisions, but CPI is used for Social Security adjustments and is more widely cited in the media.

How can I protect my money from inflation?

Key strategies include: investing in stocks (S&P 500 averages ~10% annual returns vs ~3% inflation), buying I Bonds or TIPS from the US Treasury, investing in real estate (property values tend to rise with inflation), diversifying into commodities, and negotiating salary raises that match or exceed inflation. Keeping large amounts in low-interest savings accounts is one of the worst strategies during inflationary periods.

What is the Rule of 72?

The Rule of 72 is a quick way to estimate how long it takes for prices to double at a given inflation rate. Simply divide 72 by the inflation rate. At 3% inflation, prices double in approximately 72 ÷ 3 = 24 years. At 7% inflation, they double in about 10 years. This same rule works for investments: at 10% returns, your money doubles roughly every 7.2 years.

Does this calculator work for other countries?

The historical CPI data in this calculator is specifically for the United States (BLS CPI-U data from 1913-2025). However, you can use the Custom Rate mode with any country's average inflation rate. For example, the Eurozone averages about 2%, UK about 2.5%, Brazil about 5-6%, and Argentina has experienced much higher rates. The multi-currency feature lets you enter amounts in any currency.