How this calculator works
The future-cost result estimates how much you would need to buy the same basket later. The purchasing-power result shows what a fixed number of dollars in the future is worth in today’s terms. Both use a constant annual inflation rate.
Future cost = today’s amount × (1 + inflation rate)ʸP = starting amount; C = monthly contribution; G = target; r = monthly rate; n = months; y = years, where applicable.
Example you can check
At 3% annual inflation, something costing $1,000 today would cost $1,343.92 after ten years.
Assumptions & limitations
Annual compounding with a user-selected constant rate. Actual inflation changes over time and varies by category. Negative rates model deflation. This tool does not fetch live CPI data.
Common questions
Where does the inflation rate come from?
You choose it. The default is a scenario, not a live inflation reading or forecast.
Is this an investment return?
No. Use it alongside a growth calculator to understand how rising prices affect results.
Further reading: bls.gov educational guide. Our formula conventions and examples are described above.