How to use the inflation calculator
- Choose US dollars or UK pounds. The calculator uses the official consumer price index for that country.
- Enter an amount, such as the price of something or a yearly wage.
- Pick the year the amount is from and the year to compare it with. The answer is what the same amount of buying power comes to in the second year.
You can compare in either direction. Put the later year first to see what today's price would have been in an earlier year. The swap button between the years turns the question round. Copy result gives you a short summary with the index figures used, so anyone can check the sum.
The data covers 1913 to 2025 for the US and 1988 to 2025 for the UK. 2026 is not included yet: the calculator uses whole-year averages, and the 2026 average is only published after the year ends.
How it is worked out
A price index tracks the cost of the same basket of goods and services over time. To move an amount from one year to another, multiply it by the ratio of the two years' index values:
Value in year B = amount × index in year B ÷ index in year A
For example, the US index averaged 172.2 in 2000 and 321.943 in 2025. A yearly wage of $30,000 in 2000 is 30,000 × 321.943 ÷ 172.2 = $56,087.63 in 2025 money. In other words, someone earning $30,000 in 2000 would need about $56,088 in 2025 to buy the same things.
The calculator also shows the total price change between the two years (+87.0% in that example) and the average per year, the steady yearly rate that would give the same total (about 2.5% a year from 2000 to 2025). Real inflation was higher in some years and lower in others.
Worked examples
What $100 or £100 of prices in a past year comes to in 2025, using the annual averages in the calculator:
| Year | US: $100 then | UK: £100 then |
|---|---|---|
| 1970 | $829.75 | Not covered |
| 1990 | $246.32 | £247.58 |
| 2000 | $186.96 | £190.37 |
| 2010 | $147.64 | £154.81 |
| 2020 | $124.39 | £127.32 |
A UK wage of £20,000 a year in 2005 (index 78.1) is 20,000 × 138.4 ÷ 78.1 = £35,441.74 in 2025 money. If your pay today is below that figure, your wage buys less than it did then, even if the number on the payslip went up. The pay rise calculator shows a single raise against the latest yearly inflation figure.
Going backwards works the same way: $100 of 2025 prices was about $40.60 of 1990 prices.
Where the figures come from
United States: the Consumer Price Index for All Urban Consumers (CPI-U), U.S. city average, all items, from the US Bureau of Labor Statistics (series CUUR0000SA0, 1982-84=100). The calculator uses the annual averages from the BLS file of historical CPI-U figures. This is the same series the BLS's own calculator uses: "the Consumer Price Index for All Urban Consumers (CPI-U) U.S. city average series for all items, not seasonally adjusted".
One note on 2025: US figures for October 2025 were not collected during the 2025 federal government shutdown, and BLS says "The 2025 annual average for series which were not published in October 2025 will be computed as the average of the 11 index values published." The 2025 US figure here follows that official average, so a calculator using monthly figures can give a slightly different answer.
United Kingdom: the Consumer Prices Index, all items, from the Office for National Statistics (series D7BT, 2015=100), annual figures. The ONS explains how far back it goes:
"The official series for CPI started in January 1996, although estimates are available back to 1988."Office for National Statistics, Consumer price indices: a brief guide
Why the UK starts at 1988: ONS also has modelled CPI estimates for 1950 to 1988, but says they are "provided for indicative purposes only". Its long-run series that goes back to 1800 is the Retail Prices Index (RPI), and the ONS says the RPI and its derivatives "do not meet the required standard for designation as accredited official statistics". Rather than splice an indicative or older measure onto the CPI, this calculator keeps to the CPI series the ONS publishes.
Figures taken on 7 October 2026. We add each new full year once its annual average is published.
What the answer does and does not tell you
- It is an average across the whole country. The basket includes food, energy, rents, transport and much more. One item, such as a car, a bus fare or a rent in your town, may have risen far more or far less.
- Whole-year averages smooth the year. Prices in January and December of the same year can differ. Comparing annual averages gives a fair year-to-year picture, but not a month-by-month one.
- Same year in, same amount out. If both years are the same, the answer is the amount you typed, with 0% change.
- Prices can fall. In a few years, such as the early 1930s in the US, the index went down, so an amount from the year before was worth less afterwards.
Questions and answers
What is $100 in 2000 worth today?
Using the US annual averages, $100 in 2000 is about $186.96 in 2025, the latest full year in the calculator. Prices rose 87.0% over those 25 years, about 2.5% a year on average.
Why does the calculator stop at the last full year?
It uses annual average prices, and an annual average only exists once all twelve months are published. 2026 will be added when its average is out.
Which UK inflation measure does it use?
The Consumer Prices Index (CPI), series D7BT from the Office for National Statistics. The ONS also publishes CPIH, which adds owner occupiers' housing costs and which it calls the most comprehensive measure of inflation.
Can I see what an old wage is worth today?
Yes. Enter the yearly or hourly wage and the year it was paid. The answer is what you would need today to buy the same things. It does not tell you what the same job pays now.
Why is my answer different from another inflation calculator?
Some calculators use monthly figures, a different index (such as the UK RPI) or a part year. This one uses official annual averages only, so its answers are easy to check by hand with the two index values it shows.
Sources
Checked on 7 October 2026. If a rule has changed, please tell us.
- US Bureau of Labor Statistics: 2025 federal government shutdown impact on the CPI (questions and answers)
- US Bureau of Labor Statistics: CPI-U, all items, U.S. city average (series CUUR0000SA0)
- US Bureau of Labor Statistics: Historical CPI-U, August 2026 (annual averages, XLSX)
- US Bureau of Labor Statistics: CPI Inflation Calculator (series used)
- Office for National Statistics: CPI INDEX 00: ALL ITEMS 2015=100 (D7BT)
- Office for National Statistics: Consumer price indices, a brief guide
- Office for National Statistics: Consumer price inflation, historical estimates, UK, 1950 to 1988