U.K. Historical Price Converter

A single pound in 1750 may be worth more than an entire roll of 50-pound notes.

The U.K. Historical Price converter calculates a price comparison between the money of different dates.

• UK Inflation Calculator since 1751.
• U.K. Future Inflation Calculator

“Put another way, the index shows that one decimal penny in 1750 would have had greater purchasing power than one pound in 2003.”​

Note that in the late 1700’s it took roughly £4.25 to buy an ounce of gold or £1 would buy a little less than 1/4 ounce of gold!

The Retail Prices Index (RPI)

The United Kingdom uses two different forms of measurement to calculate price inflation and the change in the value of the British Pound. The first method is called the Retail Prices Index (RPI) and it was instituted in June of 1947.

​The Consumer Price Index (CPI)

The second measurement is called the Consumer Price Index (CPI) which was introduced in 1996. The CPI tracks prices of 600 different goods from 120,000 different retail outlets. The CPI generally results in a lower inflation number than the RPI because it uses a “geometric mean” rather than an “arithmetic mean” as its method of calculation. For more information on the
Geometric Mean see: Inflation by Decade.

One advantage of the CPI over the RPI is that when using the geometric mean if prices go up and then return to their previous level the index will also return to its previous level, which is not the case with the arithmetic mean in the RPI.

The RPI is still used in calculating some price escalations such as private corporate wage negotiations. However, it is no longer used as the basis for indexing pensions​ for government employees, rather the CPI is now used. However, the RPI is still used for various other government purposes such as calculating the amount of interest payable on index-linked securities including index-linked gilts Gilt-edged securities and social housing rent increases and we use it here because it is a constant measure all the way back to 1751.

See also:

• ​U.S. Cumulative Inflation Calculator
• U.S. Bureau of Labor Statistics Inflation Calculator
• Cost of Living calculator
• Salary Inflation Calculator