How to Calculate Inflation
What is Inflation?
An inflation calculator adjusts monetary values for inflation over time. It answers: "What would £100 in 1990 be worth today in real terms?"
Formula
Step-by-Step Guide
- 1Adjusted value = Original × (CPI_new / CPI_old)
- 2Or: Adjusted = Original × (1 + avg inflation)^years
- 3UK: Bank of England provides RPI/CPI historical data
- 4US: Bureau of Labor Statistics CPI-U
Worked Examples
Frequently Asked Questions
What is Inflation?
An inflation calculator adjusts monetary values for inflation over time. It answers: "What would £100 in 1990 be worth today in real terms?"
How accurate is the Inflation calculator?
The calculator uses the standard published formula for inflation. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Inflation calculator use?
This calculator works with inches, British pounds, watts. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Inflation calculator use?
The core formula is: Adjusted value = Original × (CPI_new / CPI_old). Each step in the calculation is shown so you can verify the result manually.
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