Every result on Dollars World comes from a formula shown on the calculator's page and, where outside data is needed, an official dataset. This page lists those datasets, how often we refresh them and the conventions the calculators follow.
The data we use
U.S. consumer prices (CPI-U)
- Source: U.S. Bureau of Labor Statistics, Consumer Price Index for All Urban Consumers (CPI-U), U.S. city average, all items, not seasonally adjusted (CUUR0000SA0), via FRED.
- Used by: the Inflation Calculator and the headline figures on our home page.
- Coverage in our copy: 1913 to September 2026 (index 336.94), refreshed November 2, 2026.
- How often: BLS publishes each month; we pull the latest figures every week.
- Conventions: a full year uses the average of its monthly index values. The current year uses the latest month published. BLS never published October 2025, so that year is averaged over the months that exist.
Price levels by country
- Source: World Bank, International Comparison Program: PPP conversion factor for household final consumption (PA.NUS.PRVT.PP) and official exchange rate, period average (PA.NUS.FCRF). World Bank data.
- Used by: The Dollar Around the World and the country figures on our home page.
- Coverage in our copy: 167 countries (156 from 2025, 7 from 2024, 4 from 2023), refreshed November 2, 2026.
- Method: a country's price level is its purchasing power parity (PPP) conversion factor divided by its market exchange rate, compared with the same ratio for the United States. That tells you how far a dollar goes there once it's changed into the local currency.
- Left out (36): countries whose latest price data is more than three years old, countries with more than one official exchange rate, and the few whose figures fall outside a plausible range.
Exchange rates
- Source: the European Central Bank's euro foreign exchange reference rates, through the free Frankfurter service.
- Used by: the Currency Converter.
- Coverage: 30 currencies, every working day since January 4, 1999. The rates printed on the converter's page are from October 30, 2026; in your browser it loads the latest.
- How often: the ECB publishes around 16:00 Central European Time on working days. Days without a rate use the last one published before them.
- Conventions: the ECB quotes every currency against the euro, so a dollar-to-yen rate is worked out through the euro. These are reference (mid-market) rates, not the rate a bank or card will give you.
Everyday prices and wages
- Source: BLS Average Price Data for the U.S. city average (eggs, bread, milk, ground beef, coffee, gasoline and electricity), BLS average hourly earnings of production and nonsupervisory workers (series CEU0500000008), and the U.S. Department of Labor'shistory of the federal minimum wage.
- Used by: the value of a dollar by year pages, the hourly wage to salary pages and the prices by year pages.
- CPI categories: U.S. Bureau of Labor Statistics: CPI-U category indexes (U.S. city average, not seasonally adjusted), via the BLS public API, for rent of primary residence, food at home, food away from home, motor vehicle insurance, used cars and trucks, from 1964. BLS CPI.
- Coverage in our copy: eggs from 1980, white bread from 1980, whole milk from 1996, ground beef from 1984, ground coffee from 1980, regular gasoline from 1976, electricity from 1979, average hourly earnings from 1964; through September 2026, refreshed November 2, 2026.
- Conventions: a past year's price or wage is the average of its monthly figures (years with fewer than ten published months are left out). "Minutes of work" divides a price by that year's average hourly earnings.
Pay by occupation
- Source: U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics (OEWS), May 2025 national estimates. BLS OEWS tables.
- Used by: the hourly wage to salary pages: the jobs that pay about each wage, and where the wage ranks among U.S. workers.
- Coverage in our copy: 706 occupations with a published national median hourly wage, and the 10th to 90th percentiles of hourly pay for all workers, refreshed September 29, 2026.
- How often: BLS publishes once a year (figures for May, released the following spring); we refresh after each release.
- Conventions: a job "pays about $X an hour" when its national median rounds to $X. Catch-all "All Other" groups are left out. The share of workers earning less than a wage is estimated along a straight line between the two published percentiles either side of it.
Rules and figures from other agencies
Calculators that depend on rules rather than a dataset, such as tax rates, deposit insurance limits or mortgage insurance, name the agency behind each figure (for example the IRS, CFPB, FDIC or Federal Reserve) in the Sources section at the bottom of the page. When those rules change, we update the page and its review date.
How the math is done
- One formula, shown on the page. Each calculator's "How it works" section states the formula it uses.
- The worked examples come from the same code as the calculator, run when the site is built, so the explanation and the calculator always agree.
- Full precision, rounded only for display. Intermediate steps aren't rounded; results are rounded when they're shown.
- Your inputs stay in your browser. Calculations run on your device. A shareable link stores your inputs in the address, not on our servers.
- Estimates, not advice. Our pages point out what a calculator leaves out, like fees, taxes or rate changes. Real results depend on details a calculator can't know.
How we check it
Our editorial policy explains how each calculator is reviewed before it goes live and when data changes. Mistakes we fix are listed in our corrections log. Spotted something wrong? Tell us.