If you only need an exact number I can tell you: 1299. In case you want to know the real answer, let me explain you in details. Many of us who are thinking about starting to learn Japanese just simply give up saying it is impossible to learn the characters. One of the goals of this article is to encourage these people. One could say that there are many characters, which are difficult to learn, but it is far from impossible.
The Bay Bridge with Mt. Fuji
As for the exact number, nobody really knows how many characters there are. However there is an official list in Japan which consists of 2230 elements. If you would like to pass the most difficult examination you will need to know these. Unfortunately this doesn't guarantee that you will not to meet any new character in your life.
So why did I say 1299? Recently I got curious about the JLPT N1 list and I decided to make a short analysis of Japanese texts. I think documents related to finance are fairly difficult to read. As such I have searched for five documents on the Internet written in Japanese.
I have found different PDFs on Japanese economy, and essay on capitalism, an interesting research document on the contribution of the Internet to the Japanese economy, the relationship between Japanese and Korean economies and an article on the effectiveness of the Trans-Pacific Partnership. These texts were written by Japanese people targeting Japanese people with advanced vocabulary and grammatical structures. Therefore their content represents the JLPT N1 level.
To make a detailed analysis of the texts above I have merged them, written in python script and eliminated the unnecessary characters such as hiraganas, katakanas, numbers, latin letters and quotation marks.
As soon as the script finished the analysis, it turned out that there were 1299 unique kanjis, which is clearly less than the Japanese Language Proficiency Test N1 level requires. This is because my data set represented only a specific topic. I suppose if I made the same thing for let's say five different topics I could get most of the kanjis, that are required for the JLPT N1 level.Read more >> 20 Japanese kanjis that are used the most
I could present the whole list here, however I don't think it would be useful, because most of the kanjis need another kanj to form a word. What's more interesting is for example the first 10 elements.
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