Methodology

Sources and methodology

Every page names its own sources. This page sets out the rules that sit behind all of them.

Every page on DigifyWorld names its own sources. This page sets out the general rules that sit behind all of them.

Where the data comes from

Two kinds of source, used for different things. A country's own government is the authority on its holidays, its currency and its official languages. An international body is the better source when the point is to compare countries, because it applies one definition across all of them.

Population and demographicsUnited Nations World Population Prospects, supplemented by national statistics offices. Mid-year estimates.

EconomyWorld Bank World Development Indicators and IMF World Economic Outlook. Nominal GDP in current US dollars.

Human developmentUNDP Human Development Report. HDI, IHDI, GDI and GII, with the report cycle stated on each page.

CurrencyISO 4217 register for codes, national central banks for currency names and status.

LanguagesNational constitutions and language legislation for official status. Unicode CLDR for script and text direction.

Public holidaysNational government gazettes and the authority responsible for declaring holidays in each country.

Digital adoptionITU for internet use. UN E-Government Development Index for online service delivery and rank.

Geography and environmentNational geographic surveys and mapping agencies, with climate descriptions drawn from national meteorological services.

EducationNational ministries of education and statistics offices, reported in each country's own measures.

Practical country infoIANA time zone database, IEC plug classification, ITU-T E.164 for dialling codes, ISO 3166 for country codes.

How figures are handled

Nothing is estimated. Where a country publishes no figure for a measure, the page shows it as not available. We do not interpolate, model or borrow from a comparable country.
Units and definitions are kept as published. Education is the clearest case: countries count their school systems differently, so their figures appear in their own wording rather than forced into a shared column that would make them look comparable when they are not.
Data years are labelled. Index values in particular are revised between report cycles, and a 2023 HDI is not the same number as a 2024 one.
Derived figures are marked as derived. Where we calculate something, such as the share of a population living below replacement fertility, the calculation is described on the page that shows it.

Known limits

Holidays set by observation move. Eid al-Fitr, Eid al-Adha and several Hindu and Buddhist festivals are given as the officially announced or best-projected date and can shift by a day on local confirmation.
Practical figures vary within a country. Mains voltage and plug types differ by building age and region. The value shown is the nominal national one.
Coverage is uneven. Some countries publish far less than others. A country with fewer figures is not an error on our side; it reflects what its authorities release.
Regional variation is summarised. Where holidays or school structures differ by state or region, the country page says so rather than pretending one rule applies everywhere.

Updates and corrections

Datasets are refreshed as their publishers release new editions, which for most annual series means once a year. Holiday calendars are reviewed ahead of each calendar year.

If you find a figure that is wrong, out of date, or attributed to the wrong source, tell us through the contact page. Point us at the official source where you can, and we will check it and correct the page.