- Hiragana and katakana are sorted in the order of the kana syllabary.
- English letters are sorted alphabetically. No distinction is made between uppercase and lowercase letters.
- Numbers are sorted in descending order.
- No distinction is made between half-pitch and full-pitch English characters and symbols.
- Repetition marks "
" are treated the same as the character preceding the mark. For example, "
" is treated as "
". - Other kanji, symbols, and so on are sorted in the order of their Shift-JIS codes.
The order of the kana syllabary is as follows
The rules are applied in this order:
- No distinction is made between hiragana, full-pitch katakana, and half-pitch katakana.
- Voiced sounds, semi-voiced sounds, double consonants, and contracted sounds are treated as unvoiced sounds. Long vowel sounds (
) are treated as the vowel of the previous syllable. For example:
- Voiced sound:
-> 
- Semi-voiced sound:
-> 
- Double consonant:
-> 
- Contracted sound:
-> 
- Long-vowel sound:
-> 
- Voiced sound:
- Voiced and unvoiced sounds are sorted in the following order: unvoiced sound, voiced sound, semi-voiced sound. Previous sounds have priority.
Example:
-> 
-> 
- Double consonants and contracted sounds are placed in front of unvoiced sounds. Previous sounds have priority.
Example:
-> 