Inflation Calculator
See how inflation erodes purchasing power over time. Convert past dollars to today’s value, project what things will cost in the future, and understand real vs nominal returns on your investments.
| Inflation Rate | Cumulative | $100 Becomes | Buying Power Left | Years to Double Prices |
|---|
| Year | Price Level | Buying Power of $1 | $100 Equivalent | Cumulative Inflation |
|---|
How to Use This Inflation Calculator
Pick a mode: “Past → Today’s Dollars” converts a historical amount to today’s purchasing power (what would $100 from 2000 buy today?). “Today → Future Dollars” projects what today’s money will be worth in the future (what will $100 today buy in 2040?).
Enter the dollar amount, the start and end years, and the average annual inflation rate. The US historical average is about 3.0%, but recent years (2020–2025) ran significantly higher at ~4.5%. The Federal Reserve’s target is 2.0%. Use different rates to stress-test scenarios.
The optional nominal investment return field lets you see the real (inflation-adjusted) return on your investments. If your portfolio earns 8% nominally and inflation is 3%, your real return is roughly 5% — the actual increase in purchasing power. The Real vs Nominal tab visualizes this gap.
The Inflation Formula
Exact: (1 + nominal) / (1 + inflation) − 1
Inflation compounds just like compound interest — but working against you. At 3% annual inflation, prices double roughly every 24 years. At 5%, they double in just 14.4 years. The Rule of 72 gives a quick estimate: 72 ÷ inflation rate ≈ years to double prices.
US Inflation: Historical Context
| Period | Avg Annual Inflation | $100 Start → End Value | Key Context |
|---|---|---|---|
| 1925–2025 (100 yrs) | 2.9% | $100 → $1,720 | Long-term average — includes depression, war, stagflation |
| 1980–2000 (20 yrs) | 3.7% | $100 → $207 | Post-Volcker era, gradual disinflation |
| 2000–2020 (20 yrs) | 2.1% | $100 → $152 | The “Great Moderation” — low, stable inflation |
| 2020–2025 (5 yrs) | ~4.5% | $100 → $125 | Post-COVID surge, supply chain, fiscal stimulus |
| Fed Target | 2.0% | $100 → $149 (20yr) | Official long-term goal |
If your investment earns 7% and inflation is 3%, your real return is ~4%. That 4% represents actual new purchasing power. A savings account earning 2% with 3% inflation gives you a real return of −1% — you’re losing purchasing power despite “earning” interest. Always evaluate investments in real terms. Use the compound interest calculator with a real return rate to see actual wealth growth.
How Inflation Impacts Everyday Costs
Different categories inflate at different rates. Healthcare and education have historically inflated much faster than the overall CPI, while technology has deflated (gotten cheaper). The “basket” shown in the Cost Basket tab illustrates how a fixed dollar amount buys less of each category over time.
| Category | Avg Annual Inflation | $1,000 in 2000 → 2025 | Trend |
|---|---|---|---|
| Overall CPI | 2.8% | $2,000 | Steady |
| Healthcare | 4.2% | $2,810 | Above average — rising fast |
| College Tuition | 5.0% | $3,390 | Highest — outpaces wages |
| Housing | 3.5% | $2,370 | Above average, varies by metro |
| Food | 2.8% | $2,000 | Roughly tracks CPI |
| Technology | −3.0% | $470 | Deflation — quality up, price down |
Inflation and Retirement Planning
Inflation is the silent risk in retirement. If you retire at 65 and live to 90, 25 years of even 2.5% inflation means prices nearly double. A $5,000/month lifestyle becomes $9,500/month in purchasing power terms. This is why retirement projections must account for inflation — the retirement calculator handles this automatically.
This calculator uses a flat annual rate. Real inflation fluctuates — it was 1.2% in 2020 and 9.1% in June 2022. Historical CPI data gives the most accurate past-to-present conversion. For planning purposes, using 2.5–3.5% as an assumption range covers most reasonable scenarios. The Rate Scenarios tab lets you compare outcomes across different rates.
Related Tools
| Calculator | Use It For |
|---|---|
| Compound Interest Calculator | Project real (inflation-adjusted) investment growth |
| Future Value Calculator | Project a lump sum forward with or without inflation |
| Present Value Calculator | Discount future dollars back to today’s value |
| Retirement Calculator | Full retirement plan with inflation-adjusted projections |
| Savings Goal Calculator | Adjust savings targets for future purchasing power |
| Rule of 72 Calculator | Quick estimate — years for inflation to double prices |
FAQ
What is inflation?
Inflation is the general increase in prices over time, which means each dollar buys less than it did before. It’s measured by the Consumer Price Index (CPI), which tracks the cost of a standard “basket” of goods and services. When inflation is 3%, something that cost $100 last year costs $103 this year. Over long periods, even moderate inflation compounds dramatically.
What is a good inflation rate to use for projections?
For long-term planning, 2.5–3.0% is the most commonly used range, roughly matching the US historical average and slightly above the Fed’s 2% target. For conservative projections (especially for retirement), use 3.0–3.5%. For recent-past conversions, the actual CPI data gives precise figures. The Rate Scenarios tab lets you compare across multiple assumptions.
What is real vs nominal return?
Nominal return is the headline number — what your investment statement shows (e.g., “up 8%”). Real return subtracts inflation to show your actual increase in purchasing power. If you earn 8% nominal and inflation is 3%, your real return is ~5%. Real return is the number that actually matters for wealth building, because it measures how much more stuff you can buy.
How does inflation affect retirement?
Inflation silently increases the cost of living every year. A retiree spending $60,000/year needs $80,000/year in 10 years at 3% inflation, and $108,000/year in 20 years. This is why retirement portfolios must grow — holding cash means losing purchasing power. Social Security has COLA (cost-of-living adjustments), but they often lag real inflation. Always plan retirement with inflation-adjusted projections.
Why do some prices rise faster than CPI?
The CPI is a weighted average across all categories. Individual categories inflate at very different rates. Healthcare and education have consistently outpaced general inflation (4–5%+/year) due to structural factors. Housing varies enormously by location. Technology generally deflates (gets cheaper). Your personal inflation rate depends on your spending mix.
What is the Rule of 72 for inflation?
Divide 72 by the inflation rate to estimate how many years it takes for prices to double. At 3% inflation, prices double in ~24 years. At 6%, they double in ~12 years. This mental shortcut helps you quickly gauge inflation’s long-term impact. See the Rule of 72 calculator for a dedicated tool.
Is deflation good?
Mild deflation in specific categories (like technology) is fine. Broad deflation across the economy is typically harmful — it increases the real burden of debt, discourages spending (why buy now if prices are falling?), and can trigger a deflationary spiral. This is why central banks target low positive inflation (2%) rather than 0% or negative.
How does inflation affect bonds and fixed income?
Inflation is the biggest enemy of fixed-income investors. If you buy a bond yielding 4% and inflation runs at 3%, your real return is only 1%. If inflation rises to 5%, your real return goes negative. This is why rising inflation typically causes bond prices to fall. Treasury Inflation-Protected Securities (TIPS) adjust for CPI and protect against this risk.
Key Takeaways
- Inflation compounds against you — at 3%, prices double in ~24 years. At 5%, they double in ~14 years. Even “low” inflation erodes purchasing power significantly over decades.
- Real return is what matters — always subtract inflation from your investment return to see your actual wealth growth. An 8% nominal return with 3% inflation = ~5% real growth.
- Cash loses value every day — money in a checking account earning 0% loses 2–3% of purchasing power annually. At minimum, keep savings in a high-yield savings account or short-term bonds.
- Healthcare and education inflate faster — plan for 4–5%+ annual increases in these categories, not the headline CPI number.
- Retirement planning must include inflation — a 25-year retirement at 3% inflation means your expenses roughly double. Your portfolio needs to grow to keep pace.
- Use 2.5–3.0% for long-term planning — this covers the historical average. Stress-test with 4%+ to see how your plan holds up in higher-inflation environments.