Learning Japanese involves understanding grammar, pronunciation, the writing system, and acquiring adequate vocabulary. While the sound system is simple to master compared with those of other languages, the writing system poses a challenge for those not used to Chinese characters. On the other hand one learns a lot about Japanese culture by studying kanji characters. Japanese students begin to learn kanji characters from their first grade of an elementary school. A guideline created by the Japanese Ministry of Education, the kyōiku kanji, specifies the 1,006 simple characters a child is to learn by the end of sixth grade. Children continue to study another 939 characters in a junior high school, which totally covers 1,945 jōyō kanji (common kanji) characters, which are usually considered sufficient for everyday life.

Japanese can be learned without studying Chinese characters. However, Japanese borrowed thousands upon thousands of words from Chinese, and for various reasons, many of these Chinese-based words are now homophones (words pronounced identically) in Japanese. This may make it necessary to learn the characters if one wants to learn an extended vocabulary, although blind Japanese people who cannot read any characters are able to function in the spoken language without problems, since most words, even if not written down, can be understood by the context. "Nihon" (にほん) can mean "two long, thin objects" (二本) as well as "Japan" (日本). However, these two words have different accents, and are distinct even in isolation.

Major universities throughout the world provide Japanese language courses, and a number of secondary and even primary schools worldwide offer courses in the language. International interest in the Japanese language dates to the 1800s but has become more prevalent following Japan's economic bubble of the 1980s and the global popularity of Japanese pop culture in the 1990s and beyond. About 2.3 million people studied the language worldwide in 2003: 900,000 South Koreans, 389,000 Chinese people, 381,000 Australians, and 140,000 Americans study Japanese in lower and higher educational institutions. In Japan, more than 90,000 foreign students study at Japanese universities and Japanese language schools, including 77,000 Chinese and 15,000 South Koreans in 2003. Furthermore, local governments and some NPO(Non Profit Organisation) groups provide free Japanese language classes for foreign residents, including Japanese Brazilians and foreign wives married to Japanese nationals.

The Japanese government provides standard tests to measure spoken and written comprehension of Japanese for second language learners; the most prominent is the Japanese Language Proficiency Test (JLPT). The Japanese External Trade Organization JETRO organizes the Business Japanese Proficiency Test, to test ability to understand Japanese in a business setting.