What Is Core Inflation?
By Markets & Investing DeskUpdated Nov 10, 2026
Definition
Core inflation is the rate at which prices rise across the economy after removing food and energy, whose prices swing sharply. In the U.S. it is reported mainly as core CPI and core PCE.
Key takeaways
- Core inflation excludes food and energy so the underlying price trend is easier to see.
- Core CPI and core PCE are the two main U.S. measures. They differ in coverage, weights and formula, so they rarely produce the same number.
- The Federal Reserve prefers the PCE index because it gives a steadier view of long-term price trends.
- Core inflation does not measure what households actually pay. Groceries, gasoline and utilities still cost what they cost.
Core inflation is the rate at which prices rise across the economy after removing food and energy, the two categories whose prices swing most sharply from month to month. In the United States it is reported mainly through two indexes: core CPI, the Consumer Price Index excluding food and energy, published by the Bureau of Labor Statistics (BLS), and core PCE, the Personal Consumption Expenditures price index excluding food and energy, published by the Bureau of Economic Analysis (BEA). The overall rate that includes everything is called headline inflation.
Why food and energy are excluded
Food and energy are consumer staples. When their prices rise, people keep buying them: a driver still fills the tank when oil climbs, and a family still buys groceries. Because demand barely adjusts, supply shocks pass straight into prices.
Those supply shocks are frequent. Crude oil, natural gas, wheat, corn and pork trade as commodities on exchanges, where speculation and news move prices quickly. A drought can cut crop yields and lift food prices within a season, and a refinery outage or geopolitical event can move gasoline prices within weeks. These moves often reverse just as fast. Including them can make the inflation rate jump around without saying much about where prices are heading over the next year or two.
Removing them leaves shelter, apparel, vehicles, medical care, education, recreation and most other services. Those prices are set more slowly, through leases, wage contracts and menu prices, so they carry more information about persistent inflation pressure.
How core inflation is calculated
Statistical agencies do not compute core inflation as a separate survey. They reweight the same price data they collect for the headline index, leaving out the food and energy components and scaling the remaining weights so they sum to 100%.
The rate itself is a percentage change in the core index level:
Year-over-year core inflation = (Core index this month ÷ Core index same month last year − 1) × 100
Reports also quote a month-over-month figure (often written “core CPI m/m”), which compares this month to last month. Analysts sometimes annualize it to see the current pace:
Annualized rate = ((1 + monthly change)¹² − 1) × 100
A 0.3% monthly rise, for example, annualizes to about 3.7%. One month is noisy, so annualizing a single reading can overstate or understate the trend.
Example of core inflation (hypothetical)
Imagine a simplified economy with a basket weighted 15% food, 10% energy and 75% everything else. Over one year:
| Category | Weight | Price change |
|---|---|---|
| Food | 15% | +6% |
| Energy | 10% | −12% |
| Everything else | 75% | +3% |
Headline inflation = (0.15 × 6%) + (0.10 × −12%) + (0.75 × 3%) = 0.9% − 1.2% + 2.25% = 1.95%
Core inflation uses only the “everything else” category, so it is 3%.
The headline number suggests inflation is cooling, but the drop comes entirely from a fall in energy prices, which could reverse next year. The core figure shows that the broad price trend is running at 3%. Flip the energy move to +12% and headline jumps to 4.35%, while core stays at 3%.
How core inflation is used
Monetary policy. Central banks set interest rates based on where inflation is likely to go, not where a single month’s energy bill landed. The Federal Reserve’s 2% inflation objective is stated in terms of headline PCE, but policymakers watch core PCE closely as a guide to that headline rate’s future path.
Wages and purchasing power. Inflation reduces what a unit of money buys. If prices rise and incomes stay flat, purchasing power falls; if wages grow faster than prices, it rises. Core inflation helps separate a lasting erosion of purchasing power from a temporary spike at the pump. Rising asset prices, such as homes and investment portfolios, can also leave some households feeling wealthier even as goods prices climb.
Markets. Bond yields, rate expectations and stock indexes often react to monthly core readings, because they shape expectations for Fed decisions. Long-run figures for the broader measure are on the U.S. inflation rate by year page.
Core CPI vs. core PCE
Both exclude food and energy, but they are built differently:
- Scope. The Consumer Price Index tracks out-of-pocket spending by urban consumers. PCE also counts spending made on households’ behalf, such as employer-provided health insurance and Medicare and Medicaid payments to providers.
- Weights. CPI weights come from a household spending survey. PCE weights come from business data tied to the national accounts used to measure GDP. Shelter carries a larger weight in CPI, so housing costs move core CPI more.
- Formula. PCE uses a chain-type formula that updates weights as consumers substitute between goods. CPI’s fixed-basket approach adjusts less for substitution.
As a result, core CPI has historically tended to run above core PCE. The BEA also blends in retail survey data and cross-checks CPI prices, which smooths irregularities and is one reason the Fed favors PCE for trend analysis.
Limitations of core inflation
- Households still pay for food and energy. For a family spending a large share of income on groceries and fuel, headline inflation is the more accurate picture of rising living costs. Core is a forecasting tool, not “real” inflation.
- Energy shocks spread. A sustained oil price increase raises shipping, airfares and production costs, and those second-round effects eventually show up inside core prices.
- Other categories can be volatile too. Used cars, airfares or other items occasionally swing as sharply as food or energy, distorting core readings.
- The exclusion is a fixed rule. Removing the same categories every month ignores which prices are actually volatile at the time. Alternative measures address this, such as the Dallas Fed’s trimmed mean PCE and the Cleveland Fed’s median CPI, which drop the most extreme price changes each month, whatever the category.
The Bottom Line
Core inflation strips food and energy out of the price index to reveal the slower, more persistent trend underneath. In the U.S. it is reported as core CPI and core PCE, with the Fed leaning on PCE. Use core to judge where inflation is heading and headline to measure what prices are actually doing to a household budget.
