Inflation Calculator
What would $100 from 2000 buy today? Compare money across years with official price indexes, or project future prices with a rate you choose.
- Official CPI data
- From 1913
- Future prices
- Private
Official annual averages from the U.S. Bureau of Labor Statistics and the UK Office for National Statistics.
Details
How to calculate inflation
Historical data or your own rate.
- 1
Choose a mode
“Historical prices” uses the US or UK consumer price index. “With an inflation rate” projects forward with any percentage.
- 2
Enter amount and years
Type the amount and pick the start and end year — or a rate and a number of years.
- 3
Read the result
See the equivalent amount, total inflation, the average yearly rate, a chart and a table for every year.
Money across time
From your grandparents’ prices to your retirement budget.
Official indexes
Annual average CPI-U from the U.S. Bureau of Labor Statistics and CPI from the UK Office for National Statistics.
More than a century
US data back to 1913, UK data back to 1988, both up to 2025.
Project the future
Enter 2 %, 3 % or any rate to see future prices and what your money will still buy.
Rates explained
Total inflation over the period and the average rate per year, side by side.
Year by year
A table with the index, the yearly inflation rate and the equivalent amount, with CSV export.
Link to your calculation
Copy a link that reopens the calculator with your numbers filled in — handy for sharing or saving a scenario.
Made for phones
Large fields, the right keyboard for numbers and a layout that fits small screens.
Private by design
Everything is calculated in your browser. Your numbers are not sent to a server.
How inflation changes what money is worth
Inflation is the general rise in prices over time, measured with a consumer price index (CPI): the cost of a fixed basket of goods and services. To move an amount between two years, multiply it by the ratio of the indexes: amount × CPI in target year ÷ CPI in start year. The US CPI-U averaged 172.2 in 2000 and 321.9 in 2025, so $100 in 2000 corresponds to $186.93 in 2025.
Small yearly rates compound into large changes. US prices rose by an average of about 2.5 % a year between 2000 and 2025, which sounds modest but adds up to 87 % in total. At 3 % a year prices double in roughly 24 years; at 5 % in about 14. That is why savings and salaries need to grow at least as fast as prices to keep their buying power.
A price index describes an average household. Your personal inflation can differ depending on what you spend on — rent, energy and food have often moved faster than the average. Different indexes (CPI-U, CPI-W, PCE in the US; CPI, CPIH and RPI in the UK) also give slightly different answers. This calculator uses the headline CPI of each country.
What steady inflation does to 100 over 20 years
| Inflation per year | Price after 20 years | Buying power of 100 |
|---|---|---|
| 1 % | 122.02 | 81.95 |
| 2 % | 148.59 | 67.30 |
| 3 % | 180.61 | 55.37 |
| 4 % | 219.11 | 45.64 |
| 5 % | 265.33 | 37.69 |
Tips
- See whether your savings rate beats inflation with the Interest Calculator.
- Plan a retirement income in today’s money with the Retirement Calculator.
- Check a single price change in percent with the Percentage Change Calculator.
- To compare a past salary with a current one, convert the old salary to today’s money first — a nominal raise can be a real pay cut.
Frequently asked questions
Can’t find your answer? Contact us — we reply quickly.
How is inflation calculated between two years?
Divide the price index of the later year by the index of the earlier year and multiply by the amount. The percentage change of the index is the total inflation for the period.
What is $100 from 2000 worth today?
About $186.93 in 2025 dollars according to the US CPI-U annual averages — total inflation of 86.9 %, or about 2.5 % a year.
Which data does the calculator use?
Annual average CPI-U (all urban consumers, 1982–84 = 100) published by the U.S. Bureau of Labor Statistics, and the UK Consumer Prices Index (2015 = 100) from the Office for National Statistics.
Why is there no data for the euro area?
The historical mode currently covers the US and the UK. For other countries, use “With an inflation rate” and enter the average rate you want to assume.
What is the difference between inflation and buying power?
They are two views of the same thing. If prices rise by 25 %, the same money buys 20 % less: buying power = 100 ÷ 1.25 = 80.
Are my numbers stored or sent anywhere?
No. The calculation runs in your browser. Your last inputs are remembered on your own device only, so the form is still filled in when you come back; use Reset to clear them.
More free calculators
Money, dates, maths, health and home projects — quick answers that are worked out in your browser.