Inflation calculator (CPI)
Use this CPI inflation rate calculator to estimate inflation between any two years. Enter an amount and years to see the equivalent amount, inflation shortfall, and inflation factor. No exchange rates.
Example (based on United States CPI): $1,000 in 2000 is equivalent to approximately $1,801 in 2025.
- Equivalent amount = A × (CPIend/CPIstart)
- Inflation factor = CPIend/CPIstart
- No external CPI APIs
See Methodology and Sources.
Enter an amount and year range to see the inflation-adjusted equivalent and buying power remaining.
Inflation loss calculator
See how inflation changes purchasing power over time. Compare two years using CPI ratios to estimate the inflation-adjusted equivalent amount, the inflation shortfall, and the cumulative inflation factor.
CPI values vary by source and methodology. This site uses locally stored CPI series and the formula in docs/DATA_MODEL.md.
Country contextTap to expand
Country context
Data coverage and source details for the CPI series used on this page.
How to interpret the results
The calculator keeps values in the same currency and adjusts only for changes in the price level, using CPI. If the inflation-adjusted equivalent is higher than the nominal amount, the difference is the inflation shortfall—how much more you’d need in the end year to match the start-year purchasing power.
The cumulative inflation factor shows how much the CPI index changed over the period. For example, an inflation factor of 1.50× means the CPI index increased by 50% from the start year to the end year, which (roughly) corresponds to prices being about 50% higher on average.
How the math works
The calculator uses CPI index ratios, as described in docs/DATA_MODEL.md:
- Equivalent amount = A × (CPIend / CPIstart)
- Inflation shortfall = equivalent amount − A
- Shortfall percent = (inflation shortfall / equivalent amount) × 100
- Inflation factor = CPIend / CPIstart
How it works (quick steps)
Pick a country, then select the start and end years from its CPI series.
The calculator keeps values in the same currency (no FX conversion).
Get the equivalent amount, inflation shortfall, and CPI factor.
Country pages and data coverage
For country-specific context (currency, CPI coverage, sources, and related preset pages), pick a country below. These pages are statically generated from /data/config.ts presets and CPI JSON files in /data/cpi.
Browse hubs
Popular country calculators
Preset shortcuts
Jump into prefilled combinations of countries, ranges, and amounts.
Compare countries
Compare CPI-based inflation between two countries over the same years. This tool keeps each currency separate and does not apply FX conversion.
Compare countriesFAQTap to expand
FAQ
Answers to common questions about CPI-based inflation loss estimates.
What does the calculator output mean?
The equivalent amount estimates what your start-year amount is worth in end-year prices. Inflation shortfall is the additional amount you’d need in the end year to match the start-year purchasing power (same currency).
What is the “cumulative inflation factor”?
It’s the CPI_end / CPI_start ratio. A factor of 2.0 means prices roughly doubled over the period (on the CPI index used).
Is this the same as exchange rates?
No. This calculator stays in the same currency and uses CPI ratios to adjust for changes in the domestic price level. It does not convert between currencies.
Why do results differ from other sites?
Different sources use different CPI series, rebasing, seasonal adjustments, and rounding. This site uses the CPI values stored in /data/cpi for each country.