# Inflation Calculator

With this US Inflation Calculator you are able to find out how the value of the USD has changed over the years.

## US CPI-U Inflation Calculator

## How the US Inflation Calculator Works

When using the US Inflation Calculator, you are able to measure how the value of the USD has changed over the years. The calculator uses data which is taken from the CPI-U (Consumer Price Index for All Urban Consumers), a database which is provided by the Bureau of Labor Statistics. This database contains information which has been tracked from the year 1913. Below is an example to demonstrate how the calculator calculates the US inflation.

### An example

If you were to spend a total of $100 at a shop in August of 2015, how much would that equate to if you were to purchase the same goods in August of 2016?

- August 2015 CPI-U index = 238.316 (CPI 1)
- August 2016 CPI-U index = 240.849 (CPI 2)
- The formula below will be used,
- August 2015 USD Value x (CPI 2 / CPI 1) = August 2016 Value
- If we implement the actual values of these,
- $100 x (240.849 / 238.316) = $100 x 1.0106 = $101.062
- Price in August 2016 = $101.062

### Calculating Annual Inflation Rates

- In this example, to calculate the inflation rate for August 2016, take its CPI of "240.849" and subtract from it last year's August 2015 CPI of "238.316".
- The result is "2.533". Divide this number by the August 2015 CPI and then multiply that by 100 and add a % sign.
- (2.533 / 238.316) x 100%
- The result is August's annual inflation rate of 1.062%.

### The US inflation calculator uses the following formulae:

To revalue a sum of money between two periods in time adjusting to the CPI use the following formula:

*Sum of money ($) times (later date index divided by earlier date index)*

e.g: $100 x (240.849 [2016]) /238.316 [2015] = $101.062

To calculate a percentage change between any two months adjusting to the CPI use the following formula:

*(later date index minus earlier date index divided by earlier date index) times 100*

e.g: (240.849 [2016] - 238.316 [2015]) / 238.316 [2015] x 100 = 1.062%

## UK CPI and RPI Inflation Calculator

After entering the appropriate information, our UK Inflation Calculator will calculate how the value of the GBP has changed over the years.

## About the UK Inflation Calculator

The ONS (Office of National Statistics) have two separate indexes to indicate products and services which are to reflect living costs. These products and services are split up and sorted into one of two indexes. Each month an analysis will be performed and the results from this analysis will be inserted into the index which it belongs.

This calculator is compatible with two separate indexes, the RPI (Retail Price Index) and the CPI (Consumer Price Index). Each of these indexes are updated once a month to provide the must up to date inflation information.

After entering the information required, the calculator will perform two calculations. One of these calculations will be calculated using the RPI and the other using the CPI.

### The UK inflation calculator uses the following formulae:

To revalue a sum of money between two periods in time adjusting to the CPI / RPI use the following formula:

*Sum of money (£) times (later date index divided by earlier date index)*

e.g., CPI inflation from August 2015 to August 2016:

£100 x (100.9 [2016]) / 100.3 [2015] = £100.598

e.g., RPI inflation from August 2015 to August 2016:

£100 x (264.4 [2016]) / 259.8 [2015] = £101.770

To calculate a percentage change between any two months adjusting to the CPI / RPI use the following formula:

*(later date index minus earlier date index divided by earlier date index) times 100*

e.g., CPI Percentage change from August 2015 to August 2016:

(100.9 [2016] - 100.3 [2015]) / 100.3 [2015] x 100 = 0.598% (CPI)

e.g., RPI Percentage change from August 2015 to August 2016:

(264.4 [2016] - 259.8 [2015]) / 259.8 [2015] x 100 = 1.770% (RPI)

You may also be interested in our GDP (Gross Domestic Product) Calculator