Inflation & Purchasing Power Calculator
Separate the future nominal cost of the same basket from the future purchasing power of a fixed nominal amount.
User inputs or hypothetical examples · Consistent units and periods · Local calculation
Results
Review or adjust your inputs, then calculate to see your results and interpretation.
Understand this calculation
Multiplication answers how much money the same basket will cost; division answers what a fixed nominal amount will buy.
See calculation method and assumptions
Formula
Inflation & Purchasing Power
Future cost of the same basket
Future purchasing power of a fixed amount
Cumulative price change
Constant annual inflation compounds into a price growth factor. Multiply today’s basket cost by this factor for its future nominal cost; divide a fixed nominal amount by the same factor for future purchasing power in today’s money.
Variables, rates and periods
- A
- Today's basket cost or a fixed nominal amount (TWD)
- π
- Constant annual inflation rate
- t
- Elapsed years
- F
- Future nominal cost of the same basket (TWD)
- P
- Purchasing power of fixed nominal money, in today's TWD
- c
- Cumulative price change over the full period
- Units
- π and c are decimal rates: 3% = 0.03; displays use percentages. t is in years, amounts in TWD; P uses today's prices and F future nominal prices.
The cumulative effect of time
- The chart holds nominal money fixed and excludes interest, taxes and investment returns.
- Fractional years use the equivalent power of the fixed annual rate, not an observed monthly price path.
Separate the future nominal cost of the same basket from the future purchasing power of a fixed nominal amount.
Worked example
- Set 10,000 USD, 3% and ten years.
- The factor is 1.03^10; cumulative inflation is about 34.3916%.
- Multiply for future cost and divide for purchasing power in today’s money.
Frequently asked questions
What about zero inflation or zero years?
The factor is one, both amounts equal the input, and cumulative inflation is zero.
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