Method & data
What the comparison measures
Two pay snapshots, annualized separately, then compared using the change in U.S. consumer prices between their months.
The four steps
- Annualize each situation. An annual salary stays as entered. For an hourly rate, annual income = rate × hours per week × weeks per year.
- Find effective hourly pay. Annual gross income ÷ (hours per week × weeks per year). For annual salaries this is a comparison measure, not a contractual hourly wage.
- Find the price ratio. CPI for the later month ÷ CPI for the earlier month. A ratio of 1.04 means consumer prices rose 4% between the two months.
- Compare purchasing power. Divide the later/earlier pay ratio by the price ratio, then subtract 1. Apply this separately to annual income and effective hourly pay.
Real change = (later pay ÷ earlier pay) ÷ (later CPI ÷ earlier CPI) − 1
“Later, in earlier dollars” means later pay divided by the price ratio. The earlier pay is already expressed in earlier dollars. We calculate with full precision and round only the displayed amounts and percentages.
How to count your hours and weeks
For an annual salary, enter the full gross annual salary and the weeks you actually work at your usual weekly schedule. If you receive $60,000 including paid vacation and work 48 weeks at 40 hours, the effective rate is $60,000 ÷ 1,920 = $31.25. Using 52 weeks instead compares pay per scheduled paid hour; choose the same interpretation on both sides.
For an hourly rate, enter the weeks for which that number of hours is paid at the stated rate. If you take four unpaid weeks, use 48 rather than 52. Paid leave can be counted as paid hours when you want a comparison per paid hour. Weekly hours and weeks can include fractions. Keep the same paid-hour or worked-hour basis in both situations. In hourly mode, the hourly result stays equal to the entered rate: the tool cannot separately count paid leave or unpaid extra hours. To compare total income against actual hours worked in those cases, use annual salary mode with total annual pay and actual working weeks.
For changing hours within a year, enter a representative average if that is a useful simplification. The tool does not model a calendar of shifts, multiple jobs, overtime premiums, bonuses, commissions, benefits, or midyear changes. When hours include unpaid work, the effective rate helps describe that time, but it does not determine overtime eligibility or legal wages.
Two different purchasing-power thresholds
Preserve annual purchasing power: earlier annual income × price ratio. This answers how much annual income would buy the same national CPI basket as before, without accounting for hours.
Preserve purchasing power per hour: earlier effective hourly pay × price ratio × later annual hours. This can be higher when you work more hours, or lower when you work fewer. Neither amount prices leisure, commute time, risk, or benefits.
The source: monthly U.S. CPI-U
Source: U.S. Bureau of Labor Statistics, Consumer Price Index. We use CUUR0000SA0: CPI for All Urban Consumers (CPI-U), U.S. city average, all items, not seasonally adjusted, 1982–84 = 100. Monthly observations are retrieved through the BLS Public Data API. The calculator shows the retrieval date and the latest available month for the data it actually uses.
The initial dataset was retrieved on November 1, 2026, covering January 2017–September 2026. October 2025 is marked unavailable by BLS due to the 2025 lapse in appropriations. Missing months are never filled from neighboring observations. New months appear after publication and a successful automatic source check.
One shared source check is attempted at most daily when the calculator is visited. If it fails, the last saved official observations remain usable, with a visible warning and retrieval date; retries are limited to once every six hours. No forecast or made-up inflation rate replaces a missing observation.
CPI-U represents an average urban consumer basket. It does not measure your personal expenses, compare states or cities, or predict future inflation. The official BLS inflation calculator uses annual averages for completed years, so it can differ from this month-to-month comparison.
BLS data are in the public domain, with the exceptions described in its copyright information. Data access is subject to the BLS API terms. This independent tool is not affiliated with or endorsed by BLS.
BLS.gov cannot vouch for the data or analyses derived from these data after the data have been retrieved from BLS.gov.
Use the result in context
All amounts are gross U.S. dollars. Taxes and deductions can change take-home pay. A positive real annual change and a negative real hourly change can coexist. A negative annual change can accompany a deliberate choice to work less. The tool reports the arithmetic and leaves that personal decision to you.
Educational estimates only; not tax, legal, or individualized financial advice.