How this is calculated
Written so a skeptical reader can check our work. Last updated September 2026.
What this tool measures — and what it doesn't
This is an income comparison: where the money you receive in a year places you among the world's people. It is not a wealth (net-worth) comparison — we never ask about assets or debts. A person with a modest salary and a paid-off house may be far wealthier than a high earner with large debts; this tool cannot tell them apart, and doesn't claim to.
The data
All distribution data comes from the World Bank's Poverty and Inequality Platform (PIP), release 20260324, expressed in 2021 purchasing-power-parity (PPP) dollars per person per day. We fetch it from the public API at api.worldbank.org/pip/v1 and store it as static files, so your calculation runs entirely in your browser:
- Global curve: the world aggregate (reporting year 2024, the latest non-forecast year) sampled at 90 poverty lines log-spaced from $0.30 to $2,000 per day. Each sample tells us what share of humanity lives below that line; together they trace the global income distribution.
- Country data: each country's most recent national household survey — mean, median, population, and the income share of each tenth of the population (decile shares). Your result page shows the survey year and whether it measured income or consumption.
- Historical curves: the same global sweep for 1990, 2000, and 2010 (45 lines each), powering the “through time” comparison.
The calculation, step by step
- Today's dollars → 2021 dollars. The data is in 2021 prices, so your entry is deflated using the US Consumer Price Index (CPI-U annual averages: 270.970 in 2021, 321.943 in 2025, the latest full year). Skipping this step would overstate your rank by roughly 19%.
- Per person. The data measures income per household member, so your entry is divided by the household size you choose.
- Per day. Divided by 365.25.
- Look up the percentile. Globally, we interpolate between the sampled poverty lines (log-linear in income). For a country, the ten decile shares give the average income of each tenth of the population; we anchor those averages at their decile midpoints and interpolate between them. Above the 90th percentile, where decile averages stop resolving, we fit a Pareto tail whose mean matches the top decile's average — the standard way to extend survey data into the upper tail.
- Respect the resolution limit. We never claim finer than the top 0.1%, globally or nationally. Surveys undercount the very richest, so an extreme income shows “top 0.1%” as a bound, not a measurement.
A worked example
| Entered | $65,000 a year, one person, world comparison |
| In 2021 dollars | $65,000 × (270.970 ÷ 321.943) ≈ $54,710 |
| Per person per day | $54,710 ÷ 365.25 ≈ $149.79 (2021 PPP) |
| Global curve lookup | ≈ 98.8% of the world lives on less |
| Result | top 1.2% of the world, by income |
The simplification you should know about
We treat your US-dollar entry as PPP dollars. For someone living in the United States this is nearly exact (the US is the PPP reference country). For someone elsewhere who converts their salary to USD at the market exchange rate, it can misstate local purchasing power — typically ranking people in cheaper countries too high and people in expensive countries too low. Tools like Giving What We Can's calculator make the same simplification; a residence-based conversion is on our list.
Other honest limitations
- Country surveys measure income in some countries and consumption in others; the two aren't identical. Your result labels which one applies.
- Survey years vary by country (the result shows the year). Older surveys describe an older economy.
- The data aims at disposable (after-tax) income, which is why we ask for take-home pay.
- Household surveys undercount the very top of the distribution everywhere; treat extreme ranks as bounds.
- Comparisons over time use constant 2021 dollars, so they are inflation-adjusted by construction.
The net of it: this is a well-grounded estimate built on the best public data that exists, not a precise personal statistic. The direction and rough magnitude of the answer are robust; the decimal is not the point.
Reproducing our numbers
Every figure derives from public PIP API endpoints (/pip-grp for the world aggregate, /pip for countries) and published BLS CPI-U annual averages. Questions, corrections, or a request for our exact query list: results@yourglobalwealthrank.com.