Regarding the rules for the preparation of passport numbers, the format and logic of different countries are different. The following are examples and brief descriptions of passport numbers in several major countries/regions. Please note that all examples are fictitious and do not involve real personal information. --- ### **1. Chinese ordinary passport** -**Format**: Start with a letter (such as G/E/S/D, etc.), followed by 8 digits or a combination of letters. -**Example**: `E12345678' or `G987654AB` -**Rule analysis**： -**The first letter **: represents the passport type. For example： -**E**: Electronic ordinary passport； -**G**: Old version of ordinary passport； -**S**: Official passport； -**D**: Diplomatic passport. -**Subsequent characters**: Usually a sequence number, it may contain a verification mechanism, and letters may be used at the end to prevent duplication. --- ### **2. U.S. passport** -**Format**: 9 digits, all numbers, no letters. -**Example**:`123456789` -**Rule analysis**： -Pure numeric sequence generation, there is no clearly disclosed verification rule. -In some cases, the old passport may start with a letter (such as `C12345678`), but the new version has been cancelled. --- ### **3. Japanese passport** -**Format **: 2 letters + 7 digits. -**Example**:'TH1234567` -**Rule analysis**： -**Initial letter**: Usually 't` (ordinary passport) or 'd` (diplomatic passport)； -**The second letter **: represents the place of issuance (if `H` may indicate Tokyo)； -**Subsequent digits**: sequence number, including check digit. --- ### **4. British passport** -**Format**: All 9 digits, the new version may contain letters. -**Example**: `123456789' or 'PA7654321` -**Rule analysis**： -The old version is pure numbers; the new version may add letter prefixes (such as `PA') to distinguish types. --- ### **5. EU countries (such as Germany)** -**Format**: Combination of letters + numbers, variable length (usually 8-9 digits). -**Example**:`C01X0000T` -**Rule analysis**： -May contain country codes (e.g. `D' for Germany), but there is no uniform standard； -Some countries have added verification codes or issued year codes. --- ###**Common features** 1. **Uniqueness**: Each number is unique worldwide to avoid duplication； 2. **Type/region identification**: Some countries distinguish the passport type or place of issuance by the first letter； 3. **Verification mechanism**: Some countries have implied check digits (for example, Chinese electronic passports may be verified with a letter at the end)； 4. **Privacy protection**: The number does not directly expose the holder's sensitive information (such as birthday and address). --- ###**Precautions** -**Fictitious example**: All the above numbers are generated by simulation and cannot be used for practical purposes； -**Avoid leakage**: Passport numbers are sensitive information and must be kept strictly confidential； -**Rule changes**: Various countries may adjust the compilation rules. For the latest information, please refer to official channels. For detailed rules for a particular country, it is recommended to check the official documents issued by the immigration or foreign affairs department of that country.