Calculator
Inflation & Purchasing Power Calculator
What it calculates
Inflation quietly erodes the purchasing power of cash. This calculator shows what a given amount of money today will be worth in real terms after a number of years at an assumed inflation rate — a reminder of why long-term savers need returns that outpace inflation.
How this inflation & purchasing power calculator works
The calculator discounts today's dollars by the assumed annual inflation rate to estimate what the same amount could buy in the future.
Formula
Future purchasing power = Today's amount ÷ (1 + inflation rate)years
Inflation affects categories differently. Housing, healthcare, education, and energy may not move in line with a broad inflation measure.
Primary specifications
Before you use the result
Assumptions
- • Inflation is constant every year.
- • The result is expressed in today's dollars.
- • Personal spending patterns can rise faster or slower than headline inflation.
Quick start
- 1. Enter the amount whose purchasing power you want to test.
- 2. Try a range of plausible inflation assumptions.
- 3. Compare the result with your expected investment return.
Inputs and units
| Input | Unit | Default |
|---|---|---|
| Amount today | US dollars | $100,000 |
| Inflation rate | percent per year | 3% |
| Years | years | 20 |
Worked example (hypothetical)
Inflation & Purchasing Power Calculator: worked example
Hypothetical example using the calculator's default inputs. The numbers are illustrative, not a forecast.
| Amount today | $100,000 |
|---|---|
| Inflation rate | 3% |
| Years | 20 |
| Future purchasing power | $55,368 |
|---|---|
| Purchasing power lost | $44,632 |
At 3% a year, $100,000 buys what about $55,368 buys today after 20 years.
How to interpret the result
The output is in today's dollars. Compare it with an expected after-tax return to judge whether savings keep pace with prices, and remember that your own spending basket can inflate faster or slower than a broad index.
Frequently asked questions
Why does inflation matter for investors?
Inflation reduces what each dollar can buy over time. If your investments don't grow faster than inflation, you lose purchasing power even as your nominal balance rises.
What inflation rate should I use?
Central banks often target around 2% annual inflation, but realized inflation varies. Testing a range — say 2% to 5% — shows how sensitive your future purchasing power is.
Will my personal inflation rate match CPI?
Not necessarily. Your spending mix can differ from the broad basket, especially for housing, healthcare, education, and energy.
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Inflation & Purchasing Power Calculator shows the arithmetic. Members get the monthly call that decides which inputs matter, plus written breakpoints when the facts move. $39/month or $249/year.
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