Inflation Calculator
See how inflation erodes buying power — historical lookups, future projections, and salary keep-up.
Project today's amount into the future
US long-run average ~3% (latest CPI: January 2026)
What It Will Cost
$1,806.11
Something costing $1,000 today will cost about that much in 20 years at 3.00% inflation.
Today's Amount
$1,000
What it costs / is worth now
Future Cost
$1,806
+80.6% over 20 yr
Future Buying Power
$554
What $1,000 buys then
The calculation
Future Cost = Amount × (1 + r)^n · Buying Power = Amount ÷ (1 + r)^n
(1 + 3.00%)^20 = 1.806
Cost vs. buying power over time
The widening gap between the two lines is the inflation tax — the erosion of cash that isn't earning at least the inflation rate.
Inflation compounds — small annual rates add up to large changes over decades. To see what an investment would need to earn just to keep pace, use the Compound Interest Calculator.
How to use this calculator
Pick a mode at the top — the inputs change to match.
Forward (default) — project today’s prices into the future.
- Enter today’s amount.
- Choose an annual inflation rate (3% is a good US baseline).
- Enter the number of years to look ahead.
Historical — compare two real years using US BLS CPI data.
- Enter the dollar amount.
- Pick the year it was from.
- Pick the year you want to compare to (any year from 1913 to the most recent full year).
Salary — keep your buying power as a wage-earner.
- Enter your current salary.
- Choose an annual inflation rate.
- Enter how many years out you’re planning. The result is the salary you’ll need to match today’s buying power.
In every mode the result cards also show the inverse: how much that amount of cash actually buys, and the total / annualised inflation between the two anchors.
How it works
Inflation compounds at the rate you set:
Future cost = Amount × (1 + r)^n Future buying power = Amount ÷ (1 + r)^n
Both come from the same factor (1 + r)^n; one multiplies, the other divides. Multiplying gives the nominal price of an item in future dollars; dividing gives the real value of cash that didn’t grow.
Inflation is the silent tax on cash — the reason “safe” money kept under the mattress steadily loses value. It is also why retirement projections need to account for both the nominal return of your portfolio and the inflation rate that’s eating away at it.
Frequently Asked Questions
What is inflation? ▾
Inflation is the rate at which the general price level rises over time. When inflation runs at 3% a year, something that costs $100 today costs about $103 next year, $106 the year after, and so on. The flip side is that the same $100 cash buys less each year — that's the loss of purchasing power.
What inflation rate should I use? ▾
The US long-run average is about 3% a year, and the Federal Reserve targets 2%. Recent years have been higher. For long-term planning a 2.5–3.5% rate is reasonable; for short-term what-ifs, use the most recent published CPI figure.
What's the difference between 'future cost' and 'future buying power'? ▾
They are two sides of the same coin. Future cost is what something that costs $X today will cost in N years (multiply by the inflation factor). Future buying power is what $X in cash today will be able to buy in N years (divide by the same factor). The first goes up over time, the second goes down.
How is inflation different from compounding? ▾
Mathematically they use the same formula — both compound a percentage rate over time. The difference is direction. Compound interest grows your money; inflation shrinks its purchasing power. An investment earning exactly the inflation rate just breaks even in real terms.
Does this calculator use historical CPI data? ▾
Yes — switch to Historical mode to look up any year between 1913 and the most recent full year. The calculator uses the US Bureau of Labor Statistics CPI-U annual averages (series CUUR0000SA0, base 1982-84 = 100). The Forward mode uses a constant rate you choose, which is the right tool for what-if planning.
What does the Historical mode do? ▾
It converts a dollar amount from one calendar year into the equivalent purchasing power of another. For example, $100 in 1950 had the same buying power as roughly $1,300 today. The math is simple: equivalent = amount × (CPI in the target year ÷ CPI in the source year). Both directions work — pick a recent year as the source to find out what an amount today was worth in older dollars.
What does the Salary mode do? ▾
It tells you what salary you'll need in N years to keep the same buying power you have today. The math is identical to Forward mode — a $60,000 salary at 3% inflation needs to reach about $107,000 in 20 years just to stand still. Useful when negotiating raises or planning long-term career income. The output is the nominal salary you need, not the real raise on top of it.
Why does a small inflation rate matter so much over decades? ▾
Because it compounds. At 3% a year, prices double in about 24 years. Over a 30-year retirement, prices roughly two-and-a-half-x — meaning a portfolio that's static in nominal terms loses well over half its real value.