Inflation Calculator (Custom Rate)

Enter an amount, a yearly inflation rate, and a number of years. See what your money will actually buy — and what you'd need in the future to match today's purchasing power.

US long-run average ≈ 3%; check the latest CPI print
Buying power of your money after 20 years
Needed then to match today's $10,000
Total price increase
Annual loss of value

How inflation erodes money

Future buying power = Amount ÷ (1 + inflation)years

At 2.7% inflation, $10,000 kept in cash for 20 years buys only what about $5,870 buys today. Flip it around: you'd need roughly $17,000 in 20 years to purchase what $10,000 purchases now.

Buying power of $10,000 over time

YearsAt 2% inflationAt 3% inflationAt 5% inflation
10$8,203$7,441$6,139
20$6,730$5,537$3,769
30$5,521$4,120$2,314

What this means for your planning

  • Cash loses by default. Money earning less than inflation shrinks in real terms every year — including most checking accounts.
  • Raises must clear inflation. A 2% raise during 3% inflation is a real pay cut. Check yours with the pay raise calculator.
  • Long-term goals need inflated targets. Retiring in 30 years on "today's $60,000 lifestyle" at 3% inflation means planning for about $145,000/year in future dollars.

Frequently asked questions

What will $10,000 be worth in 20 years?

At 2.7% average inflation, $10,000 will have the buying power of about $5,870 in current dollars. You would need roughly $17,000 then to buy what $10,000 buys today.

What inflation rate should I use for planning?

The US long-run average is close to 3%. Recent years ranged from under 2% to over 9%, so many planners test 2.5–3.5% for long horizons.

How do I protect savings from inflation?

Keep long-term money in assets that historically outpace inflation — diversified stock funds, I-bonds and TIPS (inflation-linked US bonds), or at minimum high-yield accounts paying near the inflation rate.

Is this calculator based on official CPI data?

No — it applies whatever constant rate you enter, which makes it useful for future projections and what-if scenarios. For exact historical conversions, the BLS CPI calculator uses recorded index values.

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Last updated: 2026-07-07