Real Inflation Calculator
What does money from the past cost today? Enter an amount and a month to see how much it takes in September 2026 to buy the same things, measured two ways: with our Real Inflation index (actual prices of rent, groceries, gas, health care and more) and with the official CPI-U. For example, $100 in January 2018 equals $147.69 by Real Inflation and $135.15 by CPI-U.
Latest month: September 2026.
$100 from each January, in Sep 2026 dollars
| Starting month | Real Inflation | CPI-U |
|---|---|---|
| January 2018 | $147.69 | $135.15 |
| January 2019 | $145.22 | $133.16 |
| January 2020 | $141.17 | $129.79 |
| January 2021 | $138.71 | $128.03 |
| January 2022 | $122.94 | $119.03 |
| January 2023 | $112.51 | $111.95 |
| January 2024 | $112.31 | $108.60 |
| January 2025 | $107.51 | $105.44 |
| January 2026 | $106.12 | $102.98 |
How it works
How is this calculated?
Value today = amount × (index in Sep 2026 ÷ index in the starting month). The Real Inflation index is our chained, weighted index of actual prices (Jan 2019 = 100); it starts in January 2018. CPI-U is the BLS all-items index, seasonally adjusted (FRED series CPIAUCSL), available back to January 1947. Both come from the site.json file the main page uses; CPI-U months before Jan 2018 come from our CSV.
Why are the two answers different?
CPI covers thousands of goods and services with quality and substitution adjustments. Real Inflation uses only actual dollar prices for a fixed list of everyday items, weighted heavily toward rent, fuel and health costs. See the methodology on the main page.
Can I calculate from before 2018?
Yes, with CPI-U (back to 1947). Real Inflation starts in January 2018, so for earlier months only the CPI-U answer is shown.
Can I link to a specific calculation?
Yes: add ?amount=250&from=2020-03 to this page's address.