I admittedly did not have a typical background going into my PhD: I had a good fallback since I had already been working at a FAANG, I had meaningful savings, I already had research experience, etc. This made my time in Japan significantly easier and less stressful than for many of my peers. But it was still not a walk in the park.

Doing a PhD is difficult and isolating, which is exacerbated by being an international student in an unfamiliar country. And so, while I overall very much enjoyed my time there and have freely recommended it to many people, the decision to pursue a PhD in Japan should always be considered carefully.

Background

I'm an American and did my undergraduate degree in America, and before Japan, I was a PhD student in Korea. I didn't complete my doctorate there, but left with a master's to join Google full time after an internship.

My original research area was automata theory, but at Google I work primarily on on-device language models for keyboards. I have always inhabited an area between pure research and engineering and worked hard to maintain that balance.

I knew that I wanted to finish a PhD eventually, but I had a fairly specific constraint: if possible, I wanted to keep working part time while doing it. At the time I started looking seriously at doctorate programs again, I was working from my parents' house during COVID-19. I loved dense cities, I liked being abroad, and I knew that if I was going to do another PhD, I wanted the location itself to be a meaningful part of the experience.

When I started looking into PhD programs again, I was looking for a specific combination of things: a good research fit, a program that did not require me to spend five or more years away from industry, a realistic way to keep working part time, and a place where I would actually want to live. Japan happened to fit my constraints unusually well.

Why Japan can be a good place to do a PhD

Overall, Japan has a strong academic culture, especially in STEM due to the University of Tokyo, Kyoto University, Tohoku University, and my alma mater Institute of Science Tokyo.

A flexible student visa

Japan's student visa can come with work authorization from day one, provided you file the correct paperwork. This work authorization is subject to only mild constraints, like a cap of 28 hours per week during the semester and 8 hours per day during long school breaks, as well as the exclusion of some types of work.

The ability to work part time is an incredible benefit of doing a PhD in Japan that is rare elsewhere. In America, international students can do internships, but not sustained, year-round work. Since computer science and machine learning blend academia and industry so well, not being able to do industry internships is a major setback for students elsewhere.

A PhD with a deadline

Unlike the US and Europe, which often require five or more years to complete a PhD even with a related master's, the Japanese PhD system pushes you to graduate in three years. The opportunity cost of doing a PhD is high, and having a structural time limit is helpful.

However, three years can feel too short to reach the edge of your field and produce new work. In fast-moving fields like machine learning, a shorter PhD time limit pushes students towards less risky research to mitigate the risk of taking a bet, having it fail, and not having enough time to recover.

A quickly-growing tech scene

When I first looked into moving to Japan, I would not have considered staying to work at any company other than FAANG. By the time I finished, OpenAI, Anthropic, Cohere, Hugging Face, and Sakana had opened offices in Japan, which made it feel much more viable as a post-PhD destination.

Why Japan can be a bad place to do a PhD

You went to what university?

Doing a PhD abroad doesn't always have to come with a name recognition penalty, but if you travel outside of your immediate geographic area, you quickly run into name recognition issues for all but the top, globally-recognized schools. Imagine you are applying for jobs later and the person doing the initial resume screen has never heard of Tohoku University—you will likely be passed over in favor of candidates with more familiar credentials.

To put this another way: assuming you'll be a good graduate student either way, my opinion is that the expected outcome of doing a PhD at a good-but-not-top-tier university in your home country is better than doing it at a good-but-not-top-tier university abroad (with the exception of the US), if your goal is to move back to your home country after graduation.

Unnecessary courses

At Tokyo Tech, PhD students were simply unable to take graduate-level technical courses. In order to graduate, you still have to complete dozens of credits divided into seminars, humanities, and career development courses. Though I am a native English speaker, I was required to take English presentation courses. I was also required to enroll in several "future career plans" courses that were basically a series of hour-long speeches by alumni.

You published where?

A final issue I saw more of in Japan was the emphasis on domestic journals and conferences for publishing. These publications usually appear in Japanese and may have much lighter peer review than major international venues, but they can still count toward graduation requirements. Just being a domestic rather than international venue means that most employers will discount any research published there.

Where do you want to be after the PhD?

Looking back, I believe the key question to ask yourself before you commit is: where do you want to be after your PhD? If you think you want to stay in Japan after your PhD, ask whether you're okay living in a country that's difficult to fully assimilate into, being far from friends and family, and living with the pay and the difficulty of reversing course. If your plan is to do a PhD in Japan and then leave, the primary debate is whether you're willing to risk the loss in name recognition when you return home.

Finding the right lab

The critical first step is finding a lab and a professor to work with. There should be a research fit and a personality fit. Add that you are restricting yourself to Japan, and that the fit has to go both ways, and suddenly you have very few options. Japan is a desirable country to live in, so professors are inundated with prospective student emails.

I happened to meet a graduate student from my eventual lab at a conference, had a friend in the same department, briefly visited the lab on a business trip, and later held a series of research interviews that more or less sealed the deal.

Funding the degree: MEXT and the three-year clock

I would not recommend doing your PhD in Japan if you do not have the MEXT Scholarship or something similar. Self-funded PhD students are common in Japan, so universities do not always have robust scholarships available. The MEXT scholarship generally grants tuition support, airfare to Japan, and, for doctoral students, a monthly stipend of about 145,000 yen—enough to live on, but not enough to completely remove money as a source of stress in Tokyo.

I bombed the Embassy Track interview in Atlanta. My future advisor then suggested the University Recommendation Track, which involves first applying to the university directly and asking them to refer you to MEXT. The MEXT Scholarship only guarantees funding for a three-year period, with limited opportunities for extension.

Working part time during a PhD

Overall, I would recommend trying to work part time while doing a PhD if you are in Japan, but only if you already have a strong research background and some industry experience. My specific situation was somewhat special: I transferred from being a full-time employee at Google in the US to being a part-time PhD Researcher in the Tokyo Google office working two days per week. This is not a very repeatable situation. Still, I know of many people in Japan who worked part time at interesting startups throughout their entire PhD.

Despite my lab being fairly international, there was a clear divide between the Japanese and international students. One stark difference I noticed in Japan, compared to the US and Korea, was the divide between graduate and undergraduate students. Overall, while my lab experience was very nice, the university itself offered little else in terms of socializing.

Living in Tokyo

A common sentiment among foreigners in Japan is that even if you speak perfect Japanese, you will never fully fit in. Overall, my friend group was dominated by expats. If you don't already have a support group in Japan, you must work very hard to deliberately build your friend group.

I chose to live just outside of Shibuya for proximity to work and my lab. The MEXT scholarship can provide enough money to get by, but you will have to sacrifice a lot of quality of life. Supplementing your income with a side job in tech therefore becomes a very attractive situation.

After graduating

Near the end of my PhD, I began exploring my post-graduation options. Being an expat is difficult. Both my family and my partner's family live in the US. Coupled with the uncertainty of where we would eventually want to retire and the pay differential, the benefits of moving back to the US outweighed my desire to stay in Japan.

Epilogue

Having now moved back to America, I have mixed feelings. There are good things about moving back. Still, I cannot help but miss Japan terribly. In essentially every other category, my quality of life has degraded significantly since returning home.

Re-reading this article, I feel I emphasized the negative aspects of Japan more than the good. Part of that is intentional, as people often see Japan with rose-colored glasses. So I will still conclude by encouraging people to take the risk and try out Japan if they are considering it. I can almost guarantee it will be a life-changing experience.