How Inflation Works
Put simply: inflation means the price of stuff goes up over time. A gallon of milk cost $1.44 in 1990 — it's around $4.20 in 2025. Your dollar didn't shrink, but what it can buy did.
Past Equivalent = Amount × (1 + rate)years
How Fast Does Inflation Add Up?
At 3% annual inflation:
| Years | $100 Buys | Purchasing Power Lost |
|---|---|---|
| 5 | $86.26 | 13.7% |
| 10 | $74.41 | 25.6% |
| 15 | $64.19 | 35.8% |
| 20 | $55.37 | 44.6% |
| 30 | $41.20 | 58.8% |
In 30 years at 3%, $100 buys what $41 buys today. That's the problem retirees face: you need your investments to outrun inflation, or your lifestyle erodes.
US Inflation: A Brief History
| Period | Avg Annual Rate | What Happened |
|---|---|---|
| 1914–2024 | 3.2% | Long-term average across wars, oil shocks, and recessions |
| 1970s | 7.1% | Oil embargo, wage-price spirals |
| 1980s | 5.6% | Volcker raised rates to 20% to kill inflation |
| 2000–2020 | 2.1% | Stable era; the Fed kept its 2% target |
| 2021–2023 | 6.5% | COVID stimulus + supply chain disruptions |
| 2024–2026 | ~2.8% | Cooling down but still above the 2% target |
Inflation vs. Your Savings Account
If your bank pays 0.5% APY and inflation runs at 3%, you're losing 2.5% in real purchasing power every year. High-yield savings accounts (4–5% as of 2025) help, but they're tied to the Fed rate and may drop when rates fall.
To actually beat inflation long-term, you generally need to invest in stocks, real estate, or other growth assets. The S&P 500 has returned about 10% per year historically — roughly 7% after inflation.
How to Protect Your Money
- Invest in stocks or index funds. The S&P 500 has historically returned 7% above inflation.
- Buy I Bonds or TIPS. These Treasury securities adjust their value with inflation. I Bonds are capped at $10,000/year per person.
- Own real estate. Property values and rents tend to rise with inflation.
- Avoid hoarding cash. Keep 3–6 months of expenses in savings. Invest the rest.
- Negotiate raises. If your salary doesn't keep up with inflation, you're taking a pay cut each year.
Types of Inflation
Not all inflation is the same. Understanding the type helps predict how long it will last and what to do about it:
- Demand-pull inflation: Too much money chasing too few goods. Happens during economic booms or when government stimulus is large. The Federal Reserve combats this by raising interest rates.
- Cost-push inflation: Rising production costs (energy, raw materials, wages) push prices up. Oil price shocks are a classic example. This type is harder to tame without a recession.
- Built-in inflation: The wage-price spiral. Workers demand higher wages because of inflation, which raises costs, which raises prices. Expectations of future inflation become self-fulfilling.
- Shrinkflation: The price stays the same, but the product gets smaller. That “family size” cereal box is 15% smaller than 5 years ago. This is the sneakiest form of inflation.
$100 in 2000 Buys This Much Today (by Category)
Approximate purchasing power of $100 (year 2000 dollars). Electronics have deflated due to technology advances.
Inflation and Your Financial Plan
A 3% annual inflation rate cuts the purchasing power of cash in half every 24 years. To stay ahead, your investments need to earn at least the inflation rate. Use our compound interest calculator to model growth at different real rates (nominal rate minus inflation).
Inflation also affects retirement planning significantly. If you need $50,000/year today, you’ll need about $90,000/year in 20 years at 3% inflation. Our retirement calculator accounts for this automatically. And if you’re building an emergency fund, remember that your savings goal should increase over time to keep pace with rising costs.
Frequently Asked Questions
How to Use This Inflation Calculator
Enter a dollar amount and two years (or an amount with an inflation rate and number of years). The calculator shows the equivalent purchasing power adjusted for inflation.
Formula & How It Works
Adjusted Value = Original Γ (1 + Inflation Rate)^Years. Real Value = Nominal / (1 + Inflation)^Years. The CPI-U is the most common inflation measure.
Calculation Example
$100 in 2000 has the same purchasing power as approximately $183 in 2026 (average 2.4% CPI inflation). That means the dollar lost 45% of its purchasing power.
Expert Tips
Inflation erodes purchasing power silently. Investments must earn above inflation to create real wealth. Historically, US inflation averages 2-3%/year. Assets like stocks and real estate tend to outpace inflation long-term.
What is the average inflation rate?
The US historical average is about 3.2% per year since 1914. The Federal Reserve targets 2% annually. From 2021–2023, inflation ran above 6% before cooling back toward 3%.
How does inflation affect savings?
At 3% inflation, $100 today buys roughly $74 worth of goods in 10 years. A savings account earning 0.5% loses purchasing power every year. You need returns above the inflation rate to grow wealth in real terms.
What causes inflation?
Three drivers: demand-pull (too much spending chasing limited goods), cost-push (rising production costs passed to buyers), and monetary policy (central banks increasing the money supply). COVID-era inflation was a mix of all three.
How do I protect my money from inflation?
Invest in assets that historically outpace inflation: stocks, real estate, TIPS, and I Bonds. Keeping too much cash in a regular savings account is the most common mistake people make during high-inflation periods.
What is the difference between inflation and deflation?
Inflation = prices rise, your money buys less. Deflation = prices fall, your money buys more — but it discourages spending and can trigger recessions. Most economists consider 2% inflation healthier than 0% or deflation.