Applied Rules for Characters and "Yomi"

This page provides the National Diet Library's rules for characters and "Yomi", kanji readings, used to create both bibliographic and authority data in JAPAN/MARC MARC21 format.

Rules for Characters

• 文字の取扱い基準（2021年1月）(Rules for Characters (January 2021) (PDF: 396KB)) (in Japanese)
  • 文字の取扱い基準に基づく対応を行った文字一覧（2012年1月以降） (List of Characters that Require Special Handling (after January 2012)(PDF: 1.15MB)) (in Japanese) (Last Updated 2025-10-24)

Earlier rules are available here.

• From Jan. 2012 through Dec. 2020 (PDF: 169KB) (in Japanese)
• From Apr. 2008 through Dec. 2011 (in Japanese)
• From Apr. 2002 through Mar. 2008 (in Japanese)
• From Jan. 1998 through Mar. 2002 (in Japanese)
• In or before Dec. 1997 (in Japanese)

Rules for "Yomi" (reading kanji)

• 読みの基準（2021年1月）(Rules for "Yomi" (reading kanji) (January 2021) )(PDF: 964KB) (in Japanese)(Last Updated 2025-08-12)

For earlier rules, please see Earlier rules for "Yomi" (in Japanese).