Index-linked - CPI


The Consumer Price Index (CPI) is the official measure of inflation of consumer prices of the United Kingdom.

“The CPI calculates the average price increase as a percentage for a basket of 700 different goods and services. Around the middle of each month it collects information on prices of these commodities from 120,000 different retailing outlets. Note that unlike the RPI, the CPI takes the
geometric mean of prices to aggregate items at the lowest levels, instead of the arithmetic mean. This means that the CPI will generally be lower than the RPI. The rationale is that this accounts for the fact that consumers will buy less of something if its price goes up, and more if its price goes down; it also ensures that if prices go up and then revert to the previous level, the CPI also reverts to its previous level (which is not the case with the calculation method used for the RPI). According to the ONS, this difference in averaging method is the largest contributing factor to the differences between the RPI and the CPI.” (Source: Wikipedia).

For the indices since 1988 and
to calculate the CPI percentage change and apply the percentage to the rent for the adjusted figure, please visit CPI and Rent Calculator.


RPI Rent Calculator

RPI and Rent Calculator

To calculate the Retail Price Index percentage change and apply the percentage to the rent for the adjusted figure, please visit RPI and Rent Calculator.


How to use the RPI and Rent Calculator:


The pre-set display in each field is for example only. As soon as you click in a field, the preset will disappear.

To calculate the Retail Price Index (RPI) percentage change, enter the RPI figures for the start and end months. The percentage change for that period will be displayed. It's not necessary to also enter either the start month/year or end month/year: that information is simply a reminder, for your convenience.

To find out how much the rent should be to at least keep pace with the Retail Price Index (RPI), enter the rent per annum that you are receiving/paying at present. The adjusted rent will be displayed.

In the 'rent per annum' field, the rent may be entered with or without a £ sign or any commas, but the rent must be rounded to a whole number with no decimal point.

The 'rent per annum' field doesn't only have to be for rent, it may also be used for any figures such as price or cost of product or service where you want to calculate the RPI-adjusted equivalent. Although designed for yearly rent, the rent per month or any other period of time will work as well.

The calculator is for information only: no details will be stored.

Index-linked - RPI

The Retail Prices Index or Retail Price Index - RPI - is a measure of inflation published monthly by the Office for National Statistics. It measures the change in the cost of a representative sample of retail goods and services. RPI was first calculated for June 1947 and was once the principal official measure of inflation. It has been superseded by the Consumer Price Index (CPI).

For the indices since 1974 and to calculate the RPI percentage change and apply the percentage to the rent for the adjusted figure, please visit RPI and Rent Calculator.