Tokyo’s trains are too crowded for just a top 10 list, and the worst is one that runs at almost double 100-percent capacity.

Measuring how crowded something is isn’t as simple as just counting the number of people present. For example, three people isn’t considered crowded in most environments, but it definitely would be if we were talking about, say, a public restroom stall.

So in order to calculate how crowded trains are, Japan’s Ministry of Land, Infrastructure, Transport and Tourism does a quick calculation. They count all the available seats on a train, add in the number of straps standing passengers can hold onto, and call that the standard, 100-percent capacity. Then they compare that to the number of people actually on the train during rush hour, and make sure they’ve got a cup handy so they can catch their eyeballs as they pop out of their skulls in shock at how far beyond 100 percent the trains are packed.

The ministry has just released the most recent results of its annual study, and the one bit of good news is only 11 train/subway lines (all which are in the Tokyo area) were over 180-percent capacity at rush hour,  compared to 12 last year. On the other hand, that still means a ridiculously camped commute, so let’s take a look at the five most crowded:

5. Tokkaido Line: 187 percent

As with many lines on the list, the Tokkaido Line connects downtown Tokyo offices and outlying residential neighborhoods. The line runs through salaryman meccas of Tokyo, Shimbashi, and Shinagawa Stations and out to the cities of Kawasaki and Yokohama (Japan’s second-largest city) and then western Kanagawa and eastern Shizuoka Prefectures beyond.

4. Nambu Line: 189 percent

The Nambu Line may not reach the heart of Tokyo, but it runs diagonally along its southwest edge, connecting Kawasaki and Tachikawa Stations, a swath of land where some of the area’s most affordable housing is. It also connects to Musashi Kosugi Station in Kawasaki, from where trains run to both the west and east sides of downtown Tokyo.

3. Yokosuka Line: 196 percent

Like the Tokkaido Line, the Yokosuka Line’s last three stops are Tokyo, Shimbashi, and Shinagawa. At the other end, it runs through the town of Kawasaki and Yokohama, as well as historic Kamakura, beach-loving Zushi, and port town Kurihama, three cities where the price of a quiet lifestyle can sometimes be an aggravating commute into Tokyo.

2. Chuo-Sobu Line: 197 percent

So far, we’ve been looking at a lot of lines that connect Tokyo with communities to the south. The expansive Chuo Sobu Line, though, ties the city center into town to the east and west, with classy Kichijoji Mitaka (home of the Ghibli Museum) on one end, and Chiba Station, in Tokyo’s neighboring prefecture to the east, on the other. Like with the southern stops of the Yokosuka Line, these are fashionable and/or affordable places to live, but for work and school, residents hop on the Chuo Sobu Line to get to downtown’s Shinjuku, Iidabashi, Akihabara, and Ryogoku Stations.

1. Tokyo Metro Tozai Line: 199 percent

Finally, the most crowded rail line in all of Japan is actually a subway line (and yes, it’s designed as such — it’s not a train line that simply sank into the earth when it got too weighed down with passengers). The Tozai Line’s east/west endpoints are Nakano and Nishi-Funabashi, and stops between them include Takadanobaba and Waseda, home of one of downtown’s largest university campuses and multiple specialized schools, as well as Otemachi and Nihombashi, where several titans of the Japanese business and financial worlds have their main offices. Add in the fact that both Nakano and Nishi-Funabashi are transfer stations for the Chuo-Sobu line (the second-most crowded line), with some trains running straight through to the Chuo-Sobu, and it’s easy to see why it’s practically double-capacity on the Tozai at rush hour.

The remaining lines in the top 11 are:
6. Nippori Toneri Liner: 187 percent
7. Keihin Tohoku Line: 186 percent
8. Saikyo Line: 185 percent
9. Denentoshi Line: 185 percent
10. Chuo Rapid Line: 184 percent
11. Sobu Rapid Line: 18 percent

It’s also worth noting that aside from the Tozai, Nippori Toneiri, and Denentoshi Line, all the lines on the list are operated by Japan Railway (a.k.a. JR), so you might want to avoid them if you’re traveling on the all-inclusive JR pass. On the other hand, sometimes there’s no alternate route to get where you’re going, so all you can do is grit your teeth and accept the crowded trains as being one more part of the full Japan experience.

Source: Ministry of Land, Infrastructure, Transport and Tourism, Jiji via Jin
Top image: Wikipedia/DAJF
Insert images: Pakutaso, Wikipedia/STTrain, Wikipedia/Takasunrise0921, Wikipedia/本屋

Follow Casey on Twitter, where he used to ride the Tozai Line every day.