Frequently asked questions
Quick answers about using SHIZUAN and the data behind it. For the basics, start with how to read the map; for trip planning, see choosing an area to stay; if you are relocating, see checking a neighborhood before you move.
Is SHIZUAN free?
Yes. Every feature is free and there is nothing to sign up for. The site is paid for by Google AdSense ads; no ad units are placed inside the map or the data cards.
Can this map tell me how safe a place is?
No. SHIZUAN shows how many incidents were reported to the police relative to a Tokyo baseline, plus an estimate of quietness. It does not guarantee anyone's safety. Reported incidents are only the cases known to the police; they are not everything that happens and they are not the same as how a street feels at night. Please weigh the map together with the actual location, the building and recent reviews.
Where do the numbers come from?
Incidents come from the Tokyo Metropolitan Police Department's open data on reported offenses by town (Tokyo Open Data Catalog, CC BY 4.0). Population and boundaries are from the 2020 national census, zoning from the Tokyo Metropolitan Government, roads, railways, station ridership and airports from Japan's National Land Numerical Information, and counts of places to stay and late-night venues from OpenStreetMap. Retrieval dates and licenses are listed on the Data & methods page.
How recent is the data, and will it be updated?
Incident counts are the final figures for 2023 through 2025, added together. We plan to refresh them once a year, after the police publish the final numbers for the previous year.
Why do station areas and nightlife districts look so high?
Because crowds generate reports. The street layer divides by land area, so small districts that huge numbers of people pass through come out high. The residential layer divides by the number of residents, so busy districts where few people live come out even higher. Neither figure directly tells you the chance that any one person there will be a victim.
Why is so much of western Tokyo “Very low”?
Every neighborhood is compared with the same baseline: the median neighborhood in Tokyo's 23 wards. The Tama area in the west covers far more land per person, so incidents per square kilometer are low. We keep one baseline so that two neighborhoods with the same figure never get different colors just because a city boundary runs between them.
Why doesn't the map show hotel names or reviews?
SHIZUAN does not rate hotels, shops or venues. Places to stay are counted from OpenStreetMap, but no names, addresses, prices or ratings are stored or shown. To check the surroundings of a hotel you are considering, paste its map link or coordinates into the search box.
Is estimated quietness a real noise measurement?
No. It is calculated from zoning, the density of late-night venues, closeness to major roads and railways, and station ridership. It cannot account for soundproofing, the direction a room faces, or construction. See how the quietness estimate works for details.
I pasted a map link and nothing opened. Why?
Short share links do not contain a location, so they cannot be read. Show the place's coordinates in your map app and copy them, or open the short link in a browser and paste the long address it turns into. Plain coordinates such as “35.6938, 139.7034” also work.
Are my location or the links I paste sent anywhere?
No. Your location and the coordinates taken from a pasted link are used only inside your browser to find the matching neighborhood. See the privacy policy for more.
Why are some neighborhood names shown in Japanese on the English map?
English names are romanized from the official readings in Japan Post's postal code data. When a reliable reading could not be matched, we show the Japanese name rather than guess a spelling. This affects a small share of areas, mostly riverbanks, facilities and rural subdivisions.
Does the map cover the Tokyo islands or other cities?
Not at the moment. It covers the neighborhoods of mainland Tokyo only.
Can I share what I see?
Yes. Each neighborhood card has a share button that saves an image with the figures and source credits, or copies a link that reopens the same area and layer. Please keep the source credits when you share.