Inflation Calculator

An inflation calculator adjusts monetary values for inflation over time. It answers: "What would £100 in 1990 be worth today in real terms?"

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.

This calculator works with inches, British pounds, watts. You can enter values in the units shown — the calculator handles all conversions internally.

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.