Understanding Tracking Number Formats by Carrier

Every carrier has a unique tracking number format. Understanding these formats helps with carrier auto-detection, input validation, and debugging tracking issues. This guide covers the most common formats from major carriers worldwide.

Why Tracking Number Formats Matter

When a customer enters a tracking number, your application needs to:

1. Validate — Is this a real tracking number or a typo?
2. Identify the carrier — Which carrier should we query?
3. Route correctly — International numbers may need multiple carrier lookups

International Standard: S10 (UPU)

The Universal Postal Union (UPU) defines the S10 standard for international mail tracking:

Format: AALNNNNNNNNLAA
        ││         │││
        ││         ││└─ Country code (2 letters)
        ││         │└── Check digit (1 digit)
        ││         └─── Serial number (8 digits)
        │└───────────── Service indicator (1 letter)
        └────────────── Service type (1 letter)

Examples:

• EA123456789KR — Korea Post EMS
• RR987654321JP — Japan Post Registered Mail
• CP111222333US — USPS International Parcel

Service types:

Prefix	Service
EA-EZ	EMS
RA-RZ	Registered Mail
CA-CZ	Parcels
LA-LZ	Letter Post

Korean Carriers

CJ Logistics (CJ대한통운)

• Format: 10-12 digits
• Pattern: ^\\d{10,12}$
• Example: 1234567890, 123456789012

Lotte Global Logistics (롯데택배)

• Format: 12 digits
• Pattern: ^\\d{12}$
• Example: 123456789012

Hanjin Express (한진택배)

• Format: 10 or 12 digits
• Pattern: ^\\d{10}$|^\\d{12}$
• Example: 1234567890

Korea Post (우체국택배)

• Format: 13 digits (domestic) or S10 format (international)
• Pattern: ^\\d{13}$ or S10
• Example: 1234567890123, EA123456789KR

Japanese Carriers

Yamato Transport (ヤマト運輸)

• Format: 12 digits, starts with specific prefixes
• Pattern: ^\\d{12}$
• Example: 123456789012

Sagawa Express (佐川急便)

• Format: 12 digits
• Pattern: ^\\d{12}$
• Example: 123456789012

Japan Post (日本郵便)

• Format: S10 for international, 11-13 digits for domestic
• Example: RR123456789JP, 12345678901

US Carriers

USPS

• Formats vary by service:
  • Priority Mail: 22 digits (9400...)
  • Express Mail: 13 characters (S10 format)
  • Tracking: 20-22 digits

FedEx

• Format: 12, 15, or 20 digits
• Pattern: ^\\d{12}$|^\\d{15}$|^\\d{20}$
• Example: 123456789012

UPS

• Format: Starts with 1Z, 18 characters total
• Pattern: ^1Z[A-Z0-9]{16}$
• Example: 1Z12345E0205271688

European Carriers

DHL

• Format: 10 or 20 digits, may start with specific prefixes
• Pattern: ^\\d{10}$|^\\d{20}$|^[A-Z]{3}\\d{7}$
• Example: 1234567890, JJD01234567890

Royal Mail (UK)

• Format: S10 format with GB country code
• Example: RR123456789GB

Auto-Detection with WhereParcel

Instead of implementing all these patterns yourself, use WhereParcel’s auto-detection:

curl -X POST https://api.whereparcel.com/v2/track \
  -H "Authorization: Bearer YOUR_API_KEY:YOUR_SECRET_KEY" \
  -d '{"trackingItems": [{"carrier": "auto", "trackingNumber": "1Z12345E0205271688"}]}'

The API automatically identifies the carrier and returns results:

{
  "success": true,
  "data": {
    "carrier": "us.ups",
    "carrierName": "UPS",
    "trackingNumber": "1Z12345E0205271688",
    "status": "delivered"
  }
}

Validation Tips

1. Strip whitespace and dashes — Customers often copy tracking numbers with extra formatting
2. Normalize case — S10 numbers should be uppercase
3. Check length first — Quick elimination before regex matching
4. Use checksum validation — S10 numbers have a check digit you can verify

function cleanTrackingNumber(input) {
  return input
    .replace(/[\s\-\.]/g, '')  // Remove spaces, dashes, dots
    .toUpperCase()              // Normalize case
    .trim();
}

Summary

Understanding tracking number formats helps you build better tracking experiences. But instead of maintaining carrier-detection logic yourself, consider using WhereParcel’s auto-detection feature — it handles 500+ carrier formats and is updated continuously.

For the full list of supported carriers and their formats, see our Carriers documentation.