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Inflation Calculator

Measure the percent change between two CPI levels and deflate an amount into old-period purchasing power.

 

 

 

Inflation (%)
Real amount

About this calculator

Use this inflation calculator to turn two consumer-price index readings into an inflation rate and to see what a later amount would have bought in the earlier period. Both CPI values must be positive.

Inflation % = 100 × (new CPI ÷ old CPI − 1). Real amount = amount × old CPI ÷ new CPI. That real figure is the later amount expressed in old-period prices (deflated), not a forecast of future inflation.

Old CPI: Index level in the earlier period (any base year is fine if both readings share it).

New CPI: Index level in the later period.

Amount: A cash figure from the later period that you want in old prices.

Inflation (%): Percent change in the index.

Real amount: The later amount in old-period purchasing power.