Data sources

Population, area, population density, urban population, GDP, GDP per capita, GDP growth, inflation, unemployment, life expectancy, and internet usage all come from the World Bank Open Data API. For each country and indicator, we keep the most recent non-null value reported between 2018 and 2024 — not every country reports every indicator every year, so a figure might be a year or two older for some countries than others.

Not every country reports every indicator — small island nations, micro-states, and a few others are missing figures like inflation or unemployment because the World Bank itself doesn't have them on file.

Each country's official/constitutional name, currency (name, ISO 4217 code, and symbol), and official language(s) come from world-countries, an open, freely-licensed dataset that compiles ISO 4217 currency codes, ISO 639 language codes, the CIA World Factbook, and Wikipedia into one place. We fetch it live and refresh our copy from it directly, rather than keeping our own hand-typed list.

A few of these are inherently unsettled — official names can be politically contested, and currencies occasionally change faster than any dataset can track (Zimbabwe's 2024 currency reform, for one — we patch in a small number of known gaps like this by hand until the upstream dataset catches up). We do our best to keep these current and welcome a correction if you spot one out of date.

Country borders and outlines come from world-atlas (110m resolution), a TopoJSON build of Natural Earth's public domain map data. At this resolution, shapes are simplified for smooth rendering rather than surveyed precision — good for a recognizable silhouette, not for cartographic or legal boundary claims.

Each of our 365 daily facts is individually researched and cited — every fact card links to its own source (mostly Wikipedia) so you can read further or double-check it yourself.