Data sources

What this data means

Baseline data showing which areas could be inundated when a river overflows during heavy rain. It lets you compare how likely an evacuation decision may become around a property's location.

Limits & caveats

• It is a maximum-assumed-scale scenario; actual inundation depth and arrival time vary with rainfall conditions and the operation of flood-control facilities.
• Update frequency differs by municipality, so even at the same point in time there are old/new gaps between regions.

How to read it

• The map's color coding is a ranking of risk; near boundary lines, judge with a margin that allows for error.
• Check it not for the property alone but across daily routes including the nearest station, school routes, and nurseries.

What this data means

Alert-zone information for debris flows, steep-slope collapses, and the like. It is used to grasp terrain-derived risk and estimate the difficulty of evacuation during torrential rain.

Limits & caveats

• There are gaps in currency before and after a zone is designated, and even unzoned areas are not necessarily zero-risk.
• Localized measures such as ground improvement or slope-protection works may not be immediately reflected in the published data.

How to read it

• Rather than a binary of inside/outside the zone, check it together with the positional relationship to slopes and valley terrain.
• First check whether an evacuation route can be secured at night or during heavy rain.

What this data means

A wide-area indicator of how prone the ground is to liquefaction during an earthquake. It helps in comparing reclaimed land and low-lying areas.

Limits & caveats

• Because it is an estimate at the mesh level, it does not reflect micro-terrain differences within a site or a building's foundation specifications.
• Past ground-improvement history may not be incorporated into the latest data.

How to read it

• Look at the continuity with adjacent meshes and judge the risk as an area rather than a point.
• Together with hazard information, also check long-term repair costs and insurance conditions at the same time.

What this data means

Statistical data for grasping traffic-noise trends along arterial roads and the like. It serves as material for comparing the quietness of the living environment.

Limits & caveats

• Because it is based on measurement points, it does not include perceived differences arising from a building's floor level, orientation, or window performance.
• Seasonal variation in traffic volume and temporary changes due to construction are hard to capture in annual data.

How to read it

• Look at the daytime/nighttime difference and judge whether it fits your living hours.
• At a viewing, gauge it firsthand by opening/closing windows and on the balcony side, and cross-check against the statistical values.

What this data means

An indicator that estimates how easily sunlight is obtained from terrain and surrounding land use. It affects the outlook for laundry, room temperature, and electricity consumption.

Limits & caveats

• Because the individual shape of buildings and future development of neighboring lots cannot be included in the model, changes in future shadows need to be checked separately.
• Differences in solar incidence angle by season and time of day cannot be fully expressed by a single value.

How to read it

• Read elevation differences together with the density of surrounding buildings so you do not miss spots that have openings even with a low score.
• Confirming the actual daylighting during a viewing around the winter solstice improves the accuracy of your judgment.

What this data means

An indicator for wide-area comparison of ground characteristics related to how easily a site shakes. It is used for a relative assessment of perceived shaking and building-damage probability during an earthquake.

Limits & caveats

• It cannot directly evaluate the localized ground of old developed land or a building's intrinsic seismic performance.
• Because ground data is averaged, fine differences within a block may be buried.

How to read it

• Rather than the hazard alone, judge it in combination with building age, structure, and conformity to seismic standards.
• Use it to prioritize among candidate locations, and supplement the final decision with an expert inspection or the statement of important matters.

What this data means

Nationwide data classifying land use — building land, farmland, forest, water surface and so on — into a 100 m mesh. It is used to grasp how open the surroundings are and the surrounding land use that underlies daily convenience.

Limits & caveats

• Because it is the FY2021 edition, later land development, residential conversion, and newly built large facilities are not reflected.
• It is a representative category per 100 m mesh, so uses mixed within a mesh (for example a small factory inside a residential area) are buried.
• The distances to the nearest facilities shown under daily essentials are straight-line distances and do not match the walking route distance or travel time.

How to read it

• Judge by the pattern of several surrounding meshes rather than a single mesh (whether the neighbor is water or forest changes how it feels).
• Treat the distance figures as material for comparing candidate properties, and check the actual shopping and clinic routes on a map and on site.

What this data means

Statutory data showing what can be built on the land and at what scale (use district, building coverage ratio, floor area ratio), together with the zoning division such as urbanization promotion or urbanization control area. It bears on whether rebuilding will be possible and on what may go up nearby.

Limits & caveats

• Because it is the FY2019 edition, subsequent city planning changes and reviews of the zoning division are not reflected.
• Additional restrictions from district plans, building agreements, and local ordinances are not included, so the scale you can actually build needs to be checked individually.
• Near polygon boundaries, positional error of the point can attach the adjacent use district instead.

How to read it

• Urbanization control areas, unzoned white areas, and areas outside the city planning area each carry different cautions (whether rebuilding is possible / how unpredictable the surroundings are / individual checks on infrastructure).
• Always verify the final decision with the municipality's city planning division and the statement of important matters. The displayed values are for narrowing down candidates.

What this data means

Price data for actual transactions, compiled by MLIT from questionnaires to the parties to real estate transactions and similar sources (at municipality/district level). It is the basis for the estimated market price, the price distribution, and the price guides on area pages.

Limits & caveats

• It may include both transaction price information (from questionnaires) and contract price information, and Sumilca does not distinguish between the two.
• It has no coordinates and is at municipality/district level. It is an approximation from transactions in nearby municipalities, not a price at the property's exact location.
• For categories with fewer than 5 transactions we do not show the mean or median (a few transactions can swing the figure sharply).
• These are prices of transactions that have already taken place, not asking prices. They do not match the prices of properties currently listed.
• The publisher's update date cannot be obtained, so “Publisher updated” is shown as “—”.

How to read it

• Treat the estimated market price, the price distribution, and the area-page medians as a guide to whether a price is cheap or expensive. Also check whether the year, type, and area of the transactions are close to the candidate property.
• Always verify whether a price is fair against a real estate company's appraisal and the statement of important matters.