Japanese presents distinctive challenges for PII detection due to its complex writing system combining three scripts—Hiragana, Katakana, and Kanji—often mixed within single documents. Names can be written in any of these scripts or romanized, requiring detection across multiple representations. Japanese addresses follow a hierarchical structure from large to small geographical units, opposite to Western conventions. The My Number system adds a national identifier requiring careful validation to avoid false positives.
Our Japanese language processing employs specialized NLP models trained on extensive Japanese corpora. We accurately segment text without word boundaries (similar to Chinese), recognize names in all script variants, parse the unique Japanese address format, and validate Japanese-specific identifiers. This enables comprehensive PII protection for Japanese business documents, customer records, and communications.
Japanese Name Detection
Japanese names require multi-script detection capabilities:
Name Structure: Japanese names consist of a family name (姓/名字) followed by a given name (名前). Unlike Chinese names which use only Kanji, Japanese names appear in multiple forms:
- Kanji: 山田 太郎 (Yamada Tarō)
- Hiragana: やまだ たろう
- Katakana: ヤマダ タロウ
- Romaji: Yamada Taro
Name Variations:
Common patterns:
- Kanji surname + Kanji given name: 佐藤 花子
- Kanji with Hiragana reading: 田中（たなか）一郎（いちろう）
- Katakana for foreign names: マイケル・ジョンソン
- Mixed scripts: 鈴木 Mike
Spacing variations:
- With space: 山田 太郎
- Without space: 山田太郎
- Full-width space: 山田 太郎
Surname Database: We maintain comprehensive Japanese surname data:
- Top surnames covering 90%+ of population (佐藤, 鈴木, 高橋, 田中, etc.)
- Regional surnames and their variants
- Historical and noble family names
- Common given name patterns by generation and gender
My Number (マイナンバー)
Japan's national identification number system requires careful handling:
Format and Validation:
Format: 12 digits (NNNN-NNNN-NNNN or NNNNNNNNNNNN)
Check digit: Last digit is checksum
Validation algorithm:
1. Multiply first 11 digits by weights [6,5,4,3,2,7,6,5,4,3,2]
2. Sum the products
3. Calculate: 11 - (sum mod 11)
4. If result is 10 or 11, check digit is 0
5. Otherwise, result equals check digit
Example validation:
Number: 123456789018
- Weighted sum calculation
- Modulo 11 operation
- Verify check digit matches
Detection Considerations:
- Distinguish from phone numbers (10-11 digits)
- Separate from credit card numbers (16 digits)
- Handle various formatting (with/without hyphens)
- Full-width and half-width digit support
Corporate Number (法人番号):
Format: 13 digits (T + 12 digits)
- Prefix T indicates corporate entity
- Similar checksum algorithm
Example: T1234567890123
Japanese Phone Numbers
Japanese phone number formats:
Mobile Numbers:
Format: 0X0-XXXX-XXXX (11 digits starting with 070, 080, 090)
Carriers:
- 090: Original mobile prefix
- 080: Added mobile prefix
- 070: PHS and newer mobile
Examples:
090-1234-5678
080-9876-5432
070-1111-2222
Landline Numbers:
Format: (0XX) XXXX-XXXX or 0XX-XXX-XXXX
Area codes vary by region:
- Tokyo: 03
- Osaka: 06
- Nagoya: 052
- Regional: 4-digit area codes
Examples:
(03) 1234-5678 (Tokyo)
06-9876-5432 (Osaka)
0123-45-6789 (Regional)
Special Numbers:
Toll-free: 0120-XXX-XXX, 0800-XXX-XXXX
IP phones: 050-XXXX-XXXX
Emergency: 110 (Police), 119 (Fire/Ambulance)
Japanese Address Detection
Japanese addresses follow a unique hierarchical structure:
Address Hierarchy:
〒 (Postal code)
都道府県 (Prefecture)
市区町村 (City/Ward/Town/Village)
町名 (District name)
丁目 (Block number)
番地 (Building number)
号 (Unit number)
建物名・部屋番号 (Building name/Room number)
Example:
〒100-0001
東京都千代田区千代田1-1-1
皇居ビル 501号室
Components:
- 〒100-0001: Postal code
- 東京都: Tokyo Metropolis
- 千代田区: Chiyoda Ward
- 千代田: District name
- 1-1-1: Block-Building-Unit
- 皇居ビル: Building name
- 501号室: Room 501
Prefecture Types:
- 都 (to): Tokyo Metropolis (東京都)
- 道 (dō): Hokkaido (北海道)
- 府 (fu): Osaka-fu, Kyoto-fu
- 県 (ken): 43 other prefectures
Address Variations:
Full format:
東京都新宿区西新宿二丁目8番1号 都庁第一本庁舎
Abbreviated:
東京都新宿区西新宿2-8-1
With building:
〒163-8001 東京都新宿区西新宿2-8-1 都庁
Kanji vs Arabic numerals:
二丁目八番一号 = 2丁目8番1号 = 2-8-1
Japanese Writing Systems
Understanding the three scripts is essential for Japanese PII detection:
Hiragana (ひらがな):
- Phonetic script for native Japanese words
- Used for grammatical elements and readings
- 46 base characters plus combinations
- Names often written in hiragana for children or casual use
Katakana (カタカナ):
- Phonetic script for foreign words and names
- Used for emphasis (like italics)
- Foreign names typically in katakana
- Company names often mix katakana
Kanji (漢字):
- Chinese-derived logographic characters
- Most names written in kanji
- Multiple readings (on'yomi, kun'yomi) per character
- Same kanji name can have different readings
Financial Identifiers
Japanese financial documents contain specific identifiers:
Bank Account Numbers:
Format: Bank Code (4) + Branch Code (3) + Account Number (7)
Example:
銀行コード: 0001 (みずほ銀行)
支店番号: 001
口座番号: 1234567
Major bank codes:
- 0001: Mizuho Bank
- 0005: Mitsubishi UFJ
- 0009: Sumitomo Mitsui
- 0010: Resona Bank
Insurance and Pension Numbers:
Health Insurance (健康保険証):
- Insurer number: 8 digits
- Symbol/Number: Varies by insurer
Pension Number (年金番号):
- Basic Pension Number: 10 digits (4-6 format)
APPI Compliance
Japan's Act on Protection of Personal Information defines protected data:
Personal Information Categories:
- Name (氏名) - primary identifier
- Date of birth (生年月日)
- Address (住所)
- Individual Number (個人番号/マイナンバー)
- Biometric data (生体情報)
- Voice and facial recognition data
Special Care-Required Personal Information:
- Race, creed, social status
- Medical history, criminal record
- Information about being a crime victim
Anonymization Requirements: APPI specifies requirements for anonymized data (匿名加工情報) including removal of identifying elements and prevention of re-identification.
Mixed Language Processing
Japanese business documents frequently mix languages:
Example mixed document:
お客様情報:
氏名: 山田 太郎 (Yamada Taro)
Email: [email protected]
Tel: 03-1234-5678
住所: 東京都港区六本木1-1-1 Roppongi Hills Tower 25F
Detected PII:
- Japanese name: 山田 太郎
- Romanized name: Yamada Taro
- Email: [email protected]
- Phone: 03-1234-5678
- Mixed address: 東京都港区六本木1-1-1 Roppongi Hills Tower 25F
Character Width Handling
Japanese text uses both full-width and half-width characters:
Full-width (全角):
Numbers: ０１２３４５６７８９
Letters: ＡＢＣＤＥＦＧＨＩＪ
Katakana: アイウエオ
Half-width (半角):
Numbers: 0123456789
Letters: ABCDEFGHIJ
Katakana: ｱｲｳｴｵ
Both forms are detected:
電話: ０３−１２３４−５６７８ = 03-1234-5678
API Usage
Configure Japanese language processing:
POST /v1/redact
{
"text": "お客様: 山田太郎様 マイナンバー: 123456789018",
"language": "ja",
"redaction_types": ["name", "my_number", "phone", "address"]
}
Response:
{
"redacted_text": "お客様: [NAME]様 マイナンバー: [MY_NUMBER]",
"detections": [
{
"type": "name",
"value": "山田太郎",
"script": "kanji",
"confidence": 0.97
},
{
"type": "my_number",
"value": "123456789018",
"valid_checksum": true,
"confidence": 0.99
}
]
}
