How well do you know Japan’s roads?
Where are roads concentrated in Japan, and how many vehicles use them each day?
Traffic-count survey sections can be found not only around major cities such as Tokyo and Osaka, but also in mountainous areas, along the coast, and across the country from Hokkaido to Okinawa.
On the map, you can see roads clustered around large cities, roads crossing mountains to connect different areas, and roads following coastlines or running across islands.
The roads are divided into four categories. Switch between expressway-category roads (expressways and urban expressways in this dataset), general national roads, prefectural roads, and surveyed city roads, and the pattern of circles and traffic volumes changes.
This article uses Japan’s Ministry of Land, Infrastructure, Transport and Tourism Road Traffic Census to present road traffic volumes across Japan through maps and data.
Compare them with road conditions in your own country. What differences can we discover together?
How Did Traffic on Japan’s Expressway-Category Roads Change?
First, let us compare traffic on expressway-category roads in 2015 and 2021.
Here, traffic volume means the number of motor vehicles passing through each survey section in one day.
Across 2,974 comparable sections nationwide, the combined traffic volume was 122,137,049 vehicles per day in 2015 and 111,289,902 vehicles per day in 2021.
The difference was a decrease of 10,847,147 vehicles per day, or 8.9%.
This total is not the number of individual vehicles driven in Japan. If the same vehicle passes through several survey sections, it is counted once in each section.
Comparing Changes Across Nine Regions
For this article, Japan is divided into nine regions. Each region groups together several prefectures.
The rate of change in traffic volume was not the same in every region.
Hokkaido recorded a decrease of 18.7%, while the Tohoku region recorded a decrease of 15.0%.
By comparison, the Chugoku region recorded a decrease of 5.7%, and the Kyushu–Okinawa region recorded a decrease of 5.4%.
Kanto, Koshinetsu, Chubu–Hokuriku, Kinki, and Shikoku also showed different rates of change.
These figures alone do not explain why traffic changed. Start by comparing the regional differences under the same conditions.
Japan Road Traffic Volume Map
Next, use the map to explore where the roads are and how much traffic they carry.
You can switch between expressway-category roads, general national roads, prefectural roads, and surveyed city roads.
Select a circle to see the road name and traffic volume for that survey section. Switch between 2015 and 2021 to compare the same section across the two years.
This map does not show every road in Japan. It shows survey sections for which traffic volumes were published in the Ministry of Land, Infrastructure, Transport and Tourism Road Traffic Census.
How to use the map
- Use the road-category buttons to switch between expressway-category roads, general national roads, prefectural roads, and surveyed city roads.
- Areas with many circles are places where traffic-count survey sections are concentrated.
- Compare traffic volumes by the size and color of the circles.
- Select a circle to see information such as the road name, survey section, and traffic volume.
- After you select a traffic circle, the applicable official basic road section is highlighted with a fluorescent-green line and a dark outline.
- Use the search box to look for road names and other information.
Sections shown on the map
The official 2021 CSV contains 99,417 sections.
Of these, 99,067 sections whose locations could be verified in official materials are shown on the map.
The locations of the remaining 350 sections were not estimated, so those sections are not shown.
Comparison with 2015
Traffic volumes for 94,246 matching sections can be compared between 2015 and 2021.
For the 4,821 sections included only in the 2021 data, no 2015 traffic volume is shown.
Missing historical traffic volumes have not been estimated or filled in.
Follow Roads Across Japan for the First Time
In the Kanto region, home to Japan’s capital, Tokyo, circles indicating traffic volume are densely concentrated.
Move the map away from the city and you will find roads crossing mountainous areas, following the coast, and connecting places across prefectural boundaries and straits.
Even within the same road category, the pattern of circles and the traffic volumes differ from one region to another.
You do not need to know Japanese place names or road names in detail.
Start by searching for a place you know, a place you have heard of, or somewhere you plan to visit for travel or business.
Select a circle nearby, check the road name and traffic volume, and then move the map to other parts of Japan.
The map and data may help you discover a road in Japan that you have never encountered before.
Sources and Notes
- Source: Ministry of Land, Infrastructure, Transport and Tourism, 2021 Road Traffic Census: General Traffic Volume Survey (令和3年度 全国道路・街路交通情勢調査 一般交通量調査)
- Comparison years: 2015 and 2021
- The expressway-category comparison covers 2,974 matching sections for which data are available in both years. In this dataset, the category consists of expressway and urban expressway sections; it does not include general national roads.
- Traffic volume is the 24-hour motor-vehicle traffic volume for each survey section.
- Combined values are extended totals calculated by adding the traffic volume of each section. They are not counts of unique vehicles actually driven.
- Only sections whose locations could be verified in official materials are shown on the map.
- Results from the 2025 survey will be added after their official publication.