OCR for Japanese Documents: Why CJK Languages Are Harder (And How We Solved It)

Japanese documents are a worst-case scenario for classical OCR. Three writing systems mixed in one sentence (kanji, hiragana, katakana), no word boundaries, vertical text runs, and furigana annotations beside characters. A pipeline that recognizes "characters" one at a time has no context to disambiguate anything.

Why CJK breaks traditional OCR

• Thousands of kanji characters — a dictionary-based recognizer either misses rare glyphs or confuses similar ones (未 vs 末).
• Vertical and mixed-direction text: Japanese books and forms mix vertical body text with horizontal headers.
• No spaces: word segmentation must be inferred from grammar, not whitespace.
• Furigana: small pronunciation marks next to kanji confuse line-detection models.

How a VLM reads Japanese

Our parsing engine treats the page as an image and generates text with reading order. It handles vertical text, switches scripts correctly (kanji/hiragana/katakana/latin), and reconstructs the reading order of complex layouts. The language selector in the uploader lets you hint the document language — but for Japanese, even without a hint the model detects the script automatically.

The result: a Japanese contract or academic paper extracts as clean markdown, with tables and footnotes in the right place. CrazyOCR natively supports 110+ languages including Japanese, Chinese, and Korean.