Comment by glandium

It's actually mind blowing considering the tiny amount of Japanese text in the GPT-4 corpus (IIRC it's around 0.1%). But while it's better than Google Translate and DeepL, it's also not exactly great. However, it does a decent job when just talking in Japanese. I wonder how the new Japanese GPT model performs (https://openai.com/blog/introducing-openai-japan)