Inflation Calculator
Inflation & Purchasing Power Calculator works out Amount at the later price level and Increase in the amount from Work from, Base amount and Escalation / inflation rate per period. The default figures on this page give amount at the later price level of 1,343.92; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
5 steps
- Cumulative price factor = (1 + 3/100)^10 = 1.343916.
- Amount at the later price level = 1000 x 1.343916 = 1343.92.
- Total price change = (1.343916 - 1) x 100 = 34.3916%.
- The same 1000 at the later price level buys 1000 / 1.343916 = 744.09.
- Rate per period = factor^(1/10) - 1 = 3%.
Its 4 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
3 sources
Keep this result
Save it, change one figure, then compare the two
The calculation stays free. Save this scenario, adjust one assumption, save that too, and put them side by side to see exactly what the change costs you. A free account keeps 5 scenarios and 2 comparisons; Personal makes both unlimited and adds exports and private links. Nothing is saved unless you press Save.
What the Inflation & Purchasing Power Calculator calculates
Restates an amount of money at a different price level, either from an escalation rate per period or from two price-index readings, and reports the change, the annualised rate and the loss of purchasing power.
How to use this Inflation & Purchasing Power Calculator
Enter Work from, Base amount, Escalation / inflation rate per period and Number of periods. Amount at the later price level updates as you type, and “Use a worked example” loads checked figures you can adjust. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Amount at the later price level, Increase in the amount and Cumulative price factor.
The method follows Compound escalation, researched contract ESCALATION (Compound Cost Escalation Calculator), US Bureau of Labor Statistics, Consumer Price Index - Databases and calculation and US Bureau of Labor Statistics, CPI Inflation Calculator - how it works.
Research fixture R467-GT-1: 1,000 escalated at 5% for 2 periods example
With Base amount: 1000, Escalation / inflation rate per period: 5, Number of periods: 2, the calculator returns Amount at the later price level: 1102.5, Cumulative price factor: 1.1025, Rate per period (compounded): 5. This example is checked against an independent source in the test suite.
What you can compare
Change one input at a time to see how it affects Amount at the later price level, Increase in the amount and Cumulative price factor. The inputs you can vary are Work from, Base amount, Escalation / inflation rate per period, Number of periods, Index at the starting date and Index at the later date.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
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Frequently asked questions
Is there a reverse inflation calculator?
Restates an amount of money at a different price level, either from an escalation rate per period or from two price-index readings, and reports the change, the annualised rate and the loss of purchasing power. On the figures this page opens with — base amount 1,000, escalation / inflation rate per period 5% and number of periods 2 periods — the amount at the later price level is 1,343.92. Put your own figures in their place and the working updates beside the result.
What information do I need for the Inflation & Purchasing Power Calculator?
You need Work from, Base amount, Escalation / inflation rate per period, Number of periods, Index at the starting date and Index at the later date. The page opens with default figures that give amount at the later price level of 1,343.92, so you can see the scale before entering your own.
What does this Inflation & Purchasing Power Calculator show?
It shows Amount at the later price level, Increase in the amount, Cumulative price factor, Total price change, Rate per period (compounded), What the base amount still buys and Purchasing power lost, with the working and any warnings for your entries.
Can I check how the Inflation & Purchasing Power Calculator result was calculated?
Yes. The “How this is worked out” section shows the calculation steps, and the sources section identifies the references used for the method.