Inflation Adjuster Calculator

"What is $1,000 from 2000 really worth today?" sounds like one question, but this calculator can answer it three different ways, and the three answers won't quite match. That's not a bug: average, historical, and custom mode each make a different assumption about how prices actually moved year to year, and the gap between the answers is itself informative.

A Worked Example With the Calculator's Own Defaults

Run this tool exactly as it loads: $1,000, from 2000 to 2024, at a flat 2.5% in Average mode. That compounds to roughly $1,809. Now switch to Historical mode for the same range. Instead of one flat rate, it replays the actual recorded rate for each of those 24 years, including the mild deflation dip of -0.4% in 2009, and lands around $1,801. The two numbers are close because 2.5% happens to be a reasonable long-run average for this period, but they aren't identical, because compounding order matters, not just the average of the rates involved. A few high-inflation years back-to-back compound differently than the same rates spread evenly across the timeline.

Why You'd Reach for This Instead of a Savings Goal Calculator

A tool like the Savings Goal Calculator or the Compound Interest Calculator will tell you the nominal dollar figure your contributions will grow into, but that number quietly overstates what you'll actually be able to buy with it, because prices keep rising the entire time you're saving too. Use this Inflation Adjuster after the fact, as a deflator, to see what a projected future balance is worth in today's purchasing power. Or use it up front in reverse: decide you want the equivalent of $50,000 of today's buying power at retirement, and use it to translate that want into the larger nominal number you should actually be targeting in the other calculator.

Frequently Asked Questions

Q: Average mode and Historical mode use the same period but give different answers. Why?

Average mode compounds one flat rate every year. Historical mode replays the actual recorded rate for each individual year. Two paths can average out to a similar rate yet still land on different totals, because compounding order matters, not just the long-run average, as the worked example above shows.

Q: What happens if my date range includes a deflation year, like 2009?

Historical mode uses the negative rate on record for that specific year, such as -0.4% in 2009, which slightly reduces the running total for that one year before compounding resumes. It is not clamped to zero.

Q: I edited only a few years in Custom mode. Why do the untouched years still show a rate?

Custom mode pre-fills every year in your range with that year's historical rate, or 2.5% if none exists, as a starting point. It isn't blank until you edit it. Only the years you actually change will differ from the historical or default figures.

Q: Why can't I select a year before 1950 or after 2024?

The tool's built-in historical rate table only covers 1950 through 2024, and both the Historical Data and Custom Rates modes depend on that table to pre-populate each year, so the input range is capped to match.