Data and Sources
This page summarizes the statistics and boundary data used by JAM, their reference dates, calculations, and important limitations. The reference period displayed on each visualization should also be checked.
Statistical data
Foreign residents by prefecture (opens in a new tab)
Source details
This dataset is the Ministry of Justice's Statistics on Foreign Residents by prefecture and nationality or region. It is used for the Japan map, rankings, and prefecture details.
- Statistics table ID
- 0003147229
- Reference period
- The reference period displayed on each page
- Uses
- Japan map, rankings, and prefecture details
Prefecture population for standard display (opens in a new tab)
Source details
This is total population from the Statistics Bureau of Japan's Population Estimates. Standard population displays use values as of October 1, 2024.
- Statistics table ID
- 0003448231
- Reference period
- October 1, 2024
- Uses
- Standard population display
Historical prefecture population data (opens in a new tab)
Source details
This historical 2017 prefecture-level population source is retained for historical compatibility but is not used by the current national map, prefecture, municipality, or ranking per-100 presentation.
- Statistics table ID
- 0004021108
- Reference period
- October 1, 2017 (historical)
- Uses
- Historical compatibility only
Municipality foreign residents and composition (opens in a new tab)
Source details
This is the December 2025 municipality-level release of the Ministry of Justice's Statistics on Foreign Residents, delivered as an official Excel table. It is used for municipality maps, lists, and nationality composition.
- Statistics table ID
- 000040472266
- Reference period
- December 2025
- Uses
- Municipality maps, lists, and composition
Municipality basic resident register population (opens in a new tab)
Source details
National map, prefecture, municipality, and ranking per-100 values use A2101 (Japanese residents), A2201 (foreign residents), and A2301 (total residents) from table 0000020201, referenced to January 1, 2025. The value is A2201 divided by A2101 times 100; it is not a percentage. It is a separate source and reference date from the December 2025 Statistics on Foreign Residents count, and the displayed count is not used as the numerator.
- Statistics table ID
- 0000020201
- Reference period
- January 1, 2025
- Uses
- National map, prefecture, municipality, and ranking per-100 values
How display data is retrieved
JAM displays the latest successfully synchronized statistical data available to the service. It is not real-time and may not reflect a source publication immediately, so also check the reference period shown with each display.
Nationalities supported by municipality statistics
Source details
Municipality statistics support the following classifications. A nationality may be selectable in the full nationality selector while still being unavailable in municipality statistics.
- Total
- South Korea
- China
- Taiwan
- Vietnam
- Philippines
- Nepal
- United States
- Brazil
How to read the displays
Count and per-100 ratio
Count and Ratio can use different sources and reference dates. Ratio is the number of foreign residents (A2201) divided by the number of Japanese residents (A2101), multiplied by 100: foreign residents per 100 Japanese residents. It is not a percentage of the total population.
Unavailable values
If a required value is unavailable, JAM displays it as unavailable rather than treating it as zero.
Ranking Change
Ranking Change compares a selected earlier period with the latest successfully synchronized period available to JAM. Absolute change is the difference between the two observed values. If either endpoint is unavailable, JAM does not treat it as zero.
Trends
Recent Trend presents available completed periods in chronological order; it does not promise that every possible year or period is present.
Long-term Trend uses six selected historical points: December 2012, December 2015, December 2018, December 2021, December 2024, and December 2025.
Boundary data
National Land Numerical Information: Administrative Area Data (opens in a new tab)
Source details
Municipality boundaries are based on the January 1, 2025 National Land Numerical Information Administrative Area Data (N03). Regional geometry is derived from the national boundary representation. Boundary data is not the source of statistical values.
Municipality boundaries are created by JAM by processing the National Land Numerical Information Administrative Area Data provided by the Ministry of Land, Infrastructure, Transport and Tourism.
JAM processes the source and provides it as map boundary data.
Use of the e-Stat API
Official Japanese notice
このサービスは、政府統計総合窓口(e-Stat)のAPI機能を使用していますが、サービスの内容は国によって保証されたものではありません。
English translation (provided by JAM)
This service uses the API functions of the Portal Site of Official Statistics of Japan (e-Stat), but the contents of this service are not guaranteed by the Government of Japan.
Data limitations
- JAM is not a real-time account of current conditions. Check the latest successfully synchronized data available to JAM and the reference period shown on each page.
- Foreign resident counts and per-100 values use separate sources and reference dates: December 2025 for counts and January 1, 2025 for the resident-register ratio.
- Municipality statistics support only some nationality classifications.
- No data does not mean zero residents. A value may be missing from the source or unavailable in the statistical classification.
- Municipality statistics and the 2025 boundary data use different reference dates, so names, administrative codes, and areas may not align.
- There may be a delay between publication by the source and completed synchronization to JAM.
- Municipality displays may be temporarily unavailable when synchronized data cannot be retrieved.
- Changes, suspension, or communication failures in external data services may prevent data from being displayed.
- JAM does not control the content, accuracy, or availability of Google Maps.