Travelling to Japan Alone (16)

Hey, im planning to travel to japan alone as a 16 year old for a 2 week stay. I have a permission slip from my parents. Will border control give me any problems or can i enter the country freely?

The will surely give you many questions.

If from a country with the visa waiver program, yes you can enter, but you are a minor and that will give you other problems. Expect questions about your schedule, where you are staying, onward travel and proof of funds - those are the basic questions you could expect.
Also, many hotels do not accept bookings from people aged under 18. As you are under 18, that is an issue. You need to check the requirements and policy of each place. Some accommodation is strictly adult only (most capsule hotels for example).

I'm travelling alone in all around Japan ! It's amazing, all going very well and chill. Enjoy!

It's not completely illegal for a foreign minor to travel alone in Japan, but you will definitely get involved in difficult situations even if you bring a permission slip written by your parents.

You seem to believe that the permission slip from your parents will work perfectly at any time and on any occasion, but as long as you are still 16, it actually won't. As other commenters have mentioned, many hotels don't allow underage people like you to make reservations alone, even if you have parental permission. If you go to a hotel and ask them to let you stay, they will simply tell you, "We are sorry, but even with your parents' document, we cannot." So, you have to search for accommodations that allow you to stay alone, but I'm not sure if there are plenty. I believe you won't do this, but never tell a lie during the reservation process such as "My parents will be with me (but actually you're planning to come alone)".
Moreover, according to similar threads in the past, some airlines also seem not to allow underage kids to buy a ticket alone, regardless of whether you have your parents' permission or not.

Can't you bring any reliable adult people (such as your parents, siblings, or relatives) as your guardians? Or aren't there any reliable people in Japan who are familiar with your parents and can take care of you during the trip? This would make your plan much easier. But if no adult would be able to help you, you will have to wait until you turn 18 or 20.

You can avoid a lot of complications by booking all your hotels before departing your country, while being truthful about your age when doing so, and by staying inside your hotel after dark.

Note that most prefectures in Japan have by-laws stating that all who are 17 or younger should not go outside their homes after 11pm even when accompanied by an adult. (For this reason, tickets for events that finish later cannot be sold to minors.)

And foreign or not, the police patrol in city centers after dark to make sure that minors aren't around for no special reason. Parents in Japan tend to walk or drive their 16-year-olds home if they happen to arrive to their stations or bus stops later in the day for reasons such as school activities or cram school.

So, traveling in Japan alone at 16 or 17 is much more complicated than traveling alone in Japan at say 18, but you can make it easier by preparing well.

From a legal perspective - a letter from your parents (in English) will mean little to most hotels.

Why? Well - Japan strangely speaks this odd language called Japanese. As such - most people at a hotel reception will have absolutely no idea what to do if a 16 year old wants to check in. Never underestimate a Japanese persons ability to not speak English. Think of it like having a letter from your parents in Chinese saying it's ok to stay in a particular hotel. Most people will have no idea what to do with you.

It may be academically possible and my knowledge of what happens at border control is limited, but I do see problems with accommodation.

In general - kids are closely watched in Japan by the police. It's true that some police might be uncomfortable speaking to non-japanese youth - but this will not always be the case.

Why is accomodation such a problem? Well - to the best of my knowledge, hotels need to let the police know when a foreigner is staying at their premises. To the best of my knowledge, this is normally done automatically for major hotels. Finding a small apartment which allows you to rent privately for 2 weeks might be your best bet but I have little knowledge on how to do this.

it is not language problem.
the reason is that a minor can't make any kind of contract without parents. any contracts made by a minor can be canceled by their parents. the same law will be applied everywhere in world.
even when a minor brings some document, still meaningless, because he/she can't prove the genuineness. everybody can make a fake document easily.
it is difficult to distinguish that he/she is a runaway minor or not. if he/she is, they need to report to police.
therefore, letting a minor alone staying in their hotels is only a risk or a trouble.

If you don't mind staying at the same place for two weeks (three would be better), there are some organizations that can arrange homestays + japanese language lessons + cultural activities (ikebana, calligraphy, visit a Japanese highschool, etc).

I did such a program, but it was handled by my school's Japanese teacher, and I don't remember the name of the specific Japanese association we went with. We had lessons or activities in the morning and free time in the afternoon. Breakfast and dinner were provided by the host family.