How to Use
Enter the amount you want to analyse.
Choose a direction: Future Value shows what X will cost later; Past Value shows what X cost before.
Set the annual inflation rate (default 3%) and the number of years.
Click Calculate to see the adjusted amount, buying power breakdown, and a year by year table.
Use Export PDF to save the results for reference.
How the Inflation Calculator Works
For Future Value, the calculator applies compound growth: FV = PV × (1 + r/100)^n, where PV is your original amount, r is the annual rate, and n is the number of years. For Past Value, it reverses the formula: PV = FV ÷ (1 + r/100)^n. Buying power retained is calculated as (PV ÷ FV) × 100, showing what percentage of original purchasing power remains after n years of inflation at rate r.
Worked Example
- You want to know what 500 will be worth in 20 years at 3% annual inflation.
- Select Future Value, enter Amount = 500, Annual Rate = 3, Years = 20.
- Formula: FV = 500 × (1.03)^20 = 500 × 1.8061 ≈ 903.06.
- The result shows you will need approximately 903 to buy what 500 buys today.
- Buying power retained = 500 ÷ 903 ≈ 55.4%, meaning your original 500 only has 55% of its current value in 20 years.
When to Use This Calculator
- Estimating future costs for long term budget planning or retirement savings
- Understanding how a fixed salary or pension loses real value over time
- Comparing historical prices to see what something cost 10 or 20 years ago
- Evaluating whether an investment return beats inflation
- Illustrating the compounding effect of inflation for educational purposes
- Negotiating inflation adjusted salary increases or contract renewals
Important Note
This calculator uses a fixed annual rate you supply and does not connect to live CPI data. Real world inflation varies year to year and differs by country, region, and product category. Results are estimates intended for planning and illustration, not for financial, tax, or legal decisions.
High vs Low Inflation Impact
Key Features
Future and Past Value Modes
Calculate either how much purchasing power decreases over future years, or work backwards to find the historical equivalent of a current price.
Year by Year Table
See the equivalent value and remaining buying power for every year in the selected period, up to 50 rows.
Purchasing Power Chart
A line chart visualises the compounding effect of inflation, making the erosion of value immediately clear.
PDF Export
Download a formatted PDF report with all summary figures and the full year by year table for records or presentations.
Privacy and Security
All calculations run entirely in your browser. No data is ever uploaded or shared.
Frequently Asked Questions
What inflation rate should I use?
Global average inflation is roughly 3% annually over the long term. The US historical average is around 3.8%. For high inflation periods or specific countries, 7 to 10%+ may be more realistic. Use the rate that best matches your scenario.
What is the difference between Future Value and Past Value?
Future Value answers 'how much will X cost in N years?' and is useful for budgeting and savings planning. Past Value answers 'what did X cost N years ago?' and is useful for historical comparisons and understanding price growth.
Why does buying power drop so steeply over long periods?
Inflation compounds annually, so the effect accelerates over time. At 3% annual inflation, prices roughly double every 24 years. At 7%, they double in about 10 years.
Does this use live CPI data?
No. This calculator uses the annual rate you provide. For a precise historical calculation based on official CPI data, use a government statistical agency's online tool. This calculator is best for planning and estimation with a chosen average rate.