How this number is made
Inflation does not change the number on the bill. It changes what the bill buys. This page discounts an amount by the inflation rate you type. The inflation page on this site grows a price forward. This one shrinks purchasing power.
- The inflation rate is an assumption, not a promise of the CPI.
- Years are how long the cash sits without earning anything.
Formula
Future purchasing power = amount ÷ (1 + inflation) ^ years.
Worked example
With the figures already in the form, what it buys later, in today’s dollars is $641.86.
Questions
What if the cash earns interest?
Then the real-return page is the one you want. This page is cash under a mattress, economically speaking.
Which inflation index?
Whichever matches the spending. A personal rate can differ from CPI. Type the one you believe.