How inflation is calculated
Inflation is the yearly rise in prices. Over several years it compounds, just like interest. Future price = amount Γ (1 + rate)years. The flip side is purchasing power: what a fixed amount can still buy falls to amount Γ· (1 + rate)years. So at 6% for 10 years, prices rise about 79%, and today's money is worth only ~56% of what it is now.
Why inflation matters for your savings
Cash that isn't earning at least the inflation rate is losing value every year, even if the number in your account doesn't change. To simply keep up, your savings need to grow at the inflation rate; to get ahead, they need to beat it. Compare with the compound interest calculator to see if your savings are outpacing inflation.
Real vs nominal returns
A "5% return" during 6% inflation is actually a β1% real return β you went backwards in buying power. Always judge investments by their real (after-inflation) return, not the headline number.
What inflation rate should I use?
Use your country's recent average. Central-bank targets are often ~2%, but actual rates vary widely β check your local figure for the years you care about.
Does this use official CPI data?
No β it's a steady-rate projection so it works for any country and any future period. Real inflation jumps around year to year, so treat the result as a well-grounded estimate.