How to use the Inflation Calculator
Enter an earlier value and a later value. This measures the percentage change between them; it does not use a live consumer price index. Enter two comparable price levels or index values from different points in time. The calculator measures the percentage change between them; it does not identify the cause of that change.
What this calculator does
Measure the percentage increase or decrease between two price levels. It is intended to make the calculation transparent and repeatable: you provide the known values, the calculator applies the relevant relationship, and the result is shown with the units or labels used by the tool.
When this tool is useful
Use the Inflation Calculator when you need a quick, repeatable check and already have the inputs requested by the page. It is useful for comparing scenarios, checking hand calculations, planning a task, or understanding how changing one input affects the result.
How the calculation works
The calculator measures the relative change from the first value to the second: (new value − old value) ÷ old value × 100.
Practical example
For example, compare a price of 100 with a later price of 108 to measure an 8% increase between the two levels.
Things to keep in mind
- A two-value percentage change is not the same as an official consumer-price inflation rate unless the inputs come from the relevant official index.
- Different price indexes cover different baskets, regions, populations, and time periods.
- For economic, legal, or contractual use, rely on the official index and methodology required for that purpose.