Non-Smoking Restaurants

I will be going to Japan this March and I was wondering about how difficult it is to find non-smoking restaurants. I am allergic to cigarettes, not deathly, but if I am in a room with cigarettes fumes I will get an intense migraine and get nauseous/maybe throw up(not good for eating lol ). I've heard that there are many with smoking an non smoking sections still, which will not work for me. Is there a good selection of 100% non-smoking restaurants in Japan? or will I have to search every one online beforehand?
Any responses are much appreciated, thank you!

If you go to any sort of Japanese chain restaurant, you should have no problem. Just say "kin en seki" to the host when you enter, and you'll likely get a seat in the non-smoking area. The smokiest places are traditional Japanese drinking/eating establishments, like local bars.

I think OP asks the restaurants where all areas are non-smoking.
I have never seen those ones.
now, airplanes are 100% non-smoking. but in old times, there are two sections, non-smoking and smoking in one plane. all restaurants are like that.
Unhappily, smokers have strong political power in Japan, although they are not sophisticated, but have one vote.

100% non-smoking restaurants are harder to find in some towns/cities. I find it easier to find them in Tokyo than other cities. Strangely, some restaurants prohibit smoking during lunch, but allow smoking for dinner. Family-oriented restaurants tend to be non-smoking. I also find more non-smoking restaurants inside of department stores (restaurants are usually located on the top floor of department stores) and in train station mall buildings.

http://www.kinen-style.com

Kinen (Kin-En) means "no-smoking" and this site gathers informations about Kin-En restaurants. Unfortunately this is only in Japanese, but this site tells there are 47,719 no-smoking restaurants in Japan.

If you're open to eating at a vegetarian restaurant, they tend to be non-smoking in Japan since their motives tend to be based around health (you'll notice that 99% of the Japanese clientele is ALWAYS young women). I'm vegan and I've been to quite a few veg restaurants in Japan and I've never encountered cigarette smoke in any of them. Of course, you definitely won't just stumble upon a veg restaurant Japan, but HappyCow is very useful for finding them, and the app can even show results based on distance from your current location. I know this is a non-answer for some people, but if the problem is severe enough...

Agree with Gregalor 100%! If you're open to vegetarian/vegan places all the ones I've tried are non smoking and many have really good food too.

If you need a hotel chain that is non-smoking, I highly recommend the Royal Park chain. They are pricier than some of the business class chains but all their rooms are non-smoking and have always been non-smoking.

Finding a non smoking Izakaya could be very difficult but other than that plenty of non smoking places. I think you'll be fine. I don't live in Tokyo (Nagoya) but around my house i have at least 4/5 restaurant fully non smoking. Tokyo should have more for sure. Also i was just in Tokyo couple of months ago, we went to eat sushi around Shibuya, place was completely non smoking.

Thanks for the replies, this helps a lot. If it makes a difference I will be staying in the Tokyo area. Also I think I should be okay on the Izakayas, I'm only 20 so I've really never drank before, although I plan to have one or two drinks at the hotel bar, it's not really a concern.

Izakayas are probably the worst offender when it comes to smoking. Just have a look from the outside in and do a little research. Some will have a non-smoking sign on the door. But not all. And some have huge street facing access, so you might be able to sit somewhere with very good natural ventilation.

Thanks for the replies, this helps a lot. If it makes a difference I will be staying in the Tokyo area. Also I think I should be okay on the Izakayas, I'm only 20 so I've really never drank before, although I plan to have one or two drinks at the hotel bar, it's not really a concern.

The one izakaya I went to in Tokyo, they put us in a separate basement dining area with just a few tables. So even though there was a huge table of salarymen doing their after-work thing upstairs, we were by ourselves in what I assume was the non-smoking section. Or maybe they were just getting the foreigners out of sight! You might be able to find a place like that, with a non-smoking section that is actually well-separated. Of course, you won't really get the authentic izakaya atmosphere in some room by yourself away from the bar.