Kanji is not the only script in the written Japanese language, in fact it’s not even the most used script by a large margin. Kanji usually makes up less than 30% of the text while kana is around 70%.[1] Both kana, which are phonetic syllabaries, are also larger than ASCII, so chances are you confused them with kanji.

1. https://core.ac.uk/download/pdf/234725928.pdf